Add On Lenses/Telephoto Converters - Even for Point and shoots

[Nicks Pics]

Some point and shoot cameras like the Canon G 15 have a screw around the base of the lens. I was curious about what it was for so I found out that you can screw adapters on there, and then filters, macro lenses, or even telephoto extenders on to the end. In theory that sounds like a great idea! Think of these points: the camera by itself has a 1.8 - 2.8, 28-140 equiv. lens with VR. With a 2x or 4.5x magnifying lens over that you would get equiv. reach of 280mm or 630mm respectively, and the maximum aperture should not be affected. Add on lenses are also very affordable because they are small and don't need to have moving parts.

So, in theory this sounds great, it is an interesting configuration I hadn't thought about before, so why is it not better known as a telephoto alternative to superzooms, 4/3s, mirrorless, and DSLR?

I am not so much interested in it for myself, since I don't have a point and shoot like the Canon G 15, and no excuse to get one, but I know someone who does have one. Have any of you had experience with this set up?

[Shadowman]

I've seen the same for smartphones.

[chauncey]

I would guess that the level of success would depend on the quality of the base lens...
check the MTF characteristics of the base lens.

[Manfred M]

the maximum aperture should not be affected

Yes it will as the aperture is defined by the focal length divided by the entrance pupil diameter. Double your focal length and change nothing else (you can't change the entrance pupil diameter), you are going to cut your maximum aperture in half. Of course, your optical quality is going drop as well plus some additional light loss due to an increased number of air / glass interfaces.

No "free lunch here", Nick, there never is...

[Geoff F]

When I went digital in 2002 with a Canon G2 there was a 1.4x extension which screwed in like that and worked reasonably well; although if I remember correctly you had to compose with the viewing screen not looking through the viewfinder.

Overall quality has probably improved a little now.

[Nicks Pics]

Thanks guys, I was mostly just curious about this, and wondering if I should suggest the idea to the person I know with the G15. Geoff, did you think it worked okay? Of course, it probably depends on quality of the components as well.

[inkista]

Back in the day, I got a lensmate for my Powershot G9 partially so I could screw on filters but mostly so I could use a dSLR hold on the G9 (not so smart to wrap your fingers around a retractable lens). I didn't want to use TCs because I'd already played with a TC on my dSLRs and supertele lens, and knew what kind of image quality hit I'd take, and just didn't want to go there with a 1/1.7"-format sensored P&S. In addition, you tend to get a P&S to go light--I don't think a lot of Powershot folks expect to be carrying additional gear with them. The lensmate worked pretty well, but there were issues with it obscuring the optical viewfinder, and causing shadows when used with the on-board flash.

Worked great with filters, though.


Powershot G9+58mm Hoya R72 infrared filter, ultrapod.

[Nicks Pics]

I had not thought of an infrared filter in this case. Do infrared photos usually turn out black and white with no color? TCs, while known for making quality worse, seem to be used by many avid photographers, so perhaps the issue is strongly related to the quality of the TC and compatibility.

[Manfred M]

I had not thought of an infrared filter in this case. Do infrared photos usually turn out black and white with no color? TCs, while known for making quality worse, seem to be used by many avid photographers, so perhaps the issue is strongly related to the quality of the TC and compatibility.

To do IR photography properly, the built-in IR filter on the sensor stack needs to be removed from the camera and an external filter, for instance a Wratten 25A, to cut out part of the visible spectrum needs to be used in front of the lens. Removing the filter is permanent, and I believe the Bayer array goes as well, so you are shooting with a B&W camera. IR focuses a bit differently than visible light; the old manual focus lengths often had a IR focus mark engraved on them, but with modern autofocus lenses, you are going to have to shoot stopped down a bit to get the IR rays to focus properly.

There are companies that do this conversion work and the last time I looked at it, this was not an inexpensive operation. The only cameras I saw this offered on was DSLRs because of ease of access to the filter. I had briefly looked at turning the D90 into an IR camera when I got the D800, but my youngest daughter "took ownership", so I did not go any further with that thought.

Can you do IR photography without doing all the conversion work; sort of. The IR cutoff filter is not perfect and a tiny amount on near IR could still be hitting the sensor. Throw on a visible light cutoff filter and do super-long exposures, and you might get something.

[inkista]

I had not thought of an infrared filter in this case. Do infrared photos usually turn out black and white with no color?

Oh, holy hell, no. I post-processed that image to be B&W. The Hoya R72 still lets in some visible light at the red end of the spectrum, so if you don't do custom white balancing in-camera, the image that comes out of the camera is heavily red.

TCs, while known for making quality worse, seem to be used by many avid photographers, so perhaps the issue is strongly related to the quality of the TC and compatibility.

A lot of TC usage comes down to subject matter (birds is a common subject for TC, because you can never get a lens that's long enough), and the quality and speed of the lens you use it on. Using a 2x TC with a pro-quality 70-200 f/2.8 lens is a different kettle of fish from using one on, say, a 18-200 superzoom.

To do IR photography properly,

...well, at least with hand-held shutter speeds...

the built-in IR filter on the sensor stack needs to be removed from the camera and an external filter, for instance a Wratten 25A, to cut out part of the visible spectrum needs to be used in front of the lens.

Or replace with a filter that allows full-spectrum light, and then putting an IR block filter on the lens.

Removing the filter is permanent, and I believe the Bayer array goes as well, so you are shooting with a B&W camera.

Actually, I don't think the Bayer array goes with the UV/IR cut filter. The color filter array is separate. And it looks like you have to scrape it off, if you want to get rid of it. You are shooting in color--which is why channel swapping gets you false color with IR post-processing.

The image I posted was with an unconverted camera. I simply used a longer shutter speed to gather enough light to make the exposure. The Hoya R72 lowers the exposure by over 10 stops, so you won't be doing handheld IR with it, unless you get it converted.

[jcuknz]

I had not thought of an infrared filter in this case. Do infrared photos usually turn out black and white with no color? TCs, while known for making quality worse, seem to be used by many avid photographers, so perhaps the issue is strongly related to the quality of the TC and compatibility.

IMO if a photo has color in it then it is not IR ....A proper IR filter passes no visible light and renders the range of brightness in the scene in shades of grey to black .... a slightly illogical stance if you think about what I wrote but I do not consider images with color as IRs. Though we cannot see it there is a range of brightness tones beyond 720mu which the camera is capable of picking up if its IR filter is not too strong as when I used my IR filter to protect my camera when shooting a solar eclipse. It still used a shutter of 1/3800 and f/7.9 [ smallest it had as a bridge camera [Nikon 5700] at full zoom.

Back in the days when we thought a x3 or even x5 zoom starting from 35mm equivalent camera was top of the line there was a case for adaptors ... but now zooms start at 25mm [equiv] and go out to x60 they really are a redundant technology and fraught with hazards from incompatibility with the camera lens. It was usually considered that the best were designed by the camera maker [ Nikon Olympus ] to match adaptor lens to camera lens and back in the days of the Nikon 5000 I know the Canadian photographer Larry Bolch often used a WA adaptor with spectacular result and his Nikon 5000.

Not having a lens thread does not stop you using filters and close-up lens as if you get them with a matching outer diameter you can cellotape them on ... watching of course that the tape doesn't retreat into the camera body on review or shut down and gum things up ...else as I did for the 5700 I found a step-up ring that matched a rim of the lens and remained clear of the body when the lens went to sleep. [ from memory] I standardised on 49mm filters/CU lens.
My second warning on this matter is that I would not mount a lens adaptor on a delicate tromboning lens and only a thin filter or CU lens. If for example you want to mount a reversed 50mm lens as I did I made a holder for it, available from SRB-Griturn.com if you are not a DIYer like me
This photo shows the rig holding a couple of adaptors which I found in a pawn shop

Adaptors are a case of been there, done it, and not to be repeated I am afraid

[jcuknz]

I think Kathy Li is glossing over the difference between 'converters' which are used with inter-changable lens cameras and 'adaptors' which are used on fixed lens cameras such as Nic's friend has and I used for a long time and still have though MFT has usurpt the bridge cameras from common use today.

Awhile back at an aviation blogsite there were a whole lot of excellent quality shots of vintage aircraft in the air taken with a Panasonic FZ200 [x24 zoom 600mm equiv.] with a x1.7 tele adaptor ...which has the advantage that even if you loose a third or half a stop from using the adaptor the camera lens is a constant f/2.8.
My older rig with the FZ50 [x12 430mm] with its Raynox 2020 x2.2 tele adaptor gives me 950mm reach with a maximum aperture of about f/4.5 which prior to getting MFT I thought was pretty good and useful.

The counter argument is that with MFT my 14-140 lens I have 280 reach and can quarter crop at much higher ISO to compensate for the slow f/5.8 maximum aperture giving me 560 reach and I could use my Olympus TCON x1.7 adaptor for 952mm reach though that means working at about f/10* but ISO helps here. All this is talking about possibilites with full automatic operation if required ... as with any ILC the field is very open for manual operations.

* Due to basic incompatibility between camera lens and adaptor I loose about 5/3 stops of light when used on the 014140 lens compared to 1/3 on my bridge cameras which are compatible. The camera lens needs to be small enough to fully use what the adaptor is supplying ... I first discovered this when I added the Raynox to my Tokina 90-230 f/4 constant lens and found that OK it gave me a x2.2 tele adaption but lost a full two stops so I was no better than if I had found a tele-converter ... which I did find later .. a couple of Pentax TCs at NZ$15 each The vendor didn't know what he had found and was selling on auction
Sorry for these two rambles but I have tried quite a few different things over the years

[jcuknz]

A lot of TC usage comes down to subject matter (birds is a common subject for TC, because you can never get a lens that's long enough), and the quality and speed of the lens you use it on. Using a 2x TC with a pro-quality 70-200 f/2.8 lens is a different kettle of fish from using one on, say, a 18-200 superzoom.
.

I think Kathy Li is glossing over the difference between 'converters' which are used with inter-changable lens cameras and 'adaptors' which are used on fixed lens cameras such as Nic's friend has and I used for a long time and still have though MFT has usurpt the bridge cameras from common use today.

Awhile back at an aviation blogsite there were a whole lot of excellent quality shots of vintage aircraft in the air taken with a Panasonic FZ200 [x24 zoom 600mm equiv.] with a x1.7 tele adaptor ...which has the advantage that even if you loose a third or half a stop from using the adaptor the camera lens is a constant f/2.8.
My older rig with the FZ50 [x12 430mm] with its Raynox 2020 x2.2 tele adaptor gives me 950mm reach with a maximum aperture of about f/4.5 which prior to getting MFT I thought was pretty good and useful.

The counter argument is that with MFT my 14-140 lens I have 280 reach and can quarter crop at much higher ISO to compensate for the slow f/5.8 maximum aperture giving me 560 reach and I could use my Olympus TCON x1.7 adaptor for 952mm reach though that means working at about f/10* but ISO helps here. All this is talking about possibilites with full automatic operation if required ... as with any ILC the field is very open for manual operations.

* Due to basic incompatibility between camera lens and adaptor I loose about 5/3 stops of light when used on the 014140 lens compared to 1/3 on my bridge cameras which are compatible. The camera lens needs to be small enough to fully use what the adaptor is supplying ... I first discovered this when I added the Raynox to my Tokina 90-230 f/4 constant lens and found that OK it gave me a x2.2 tele adaption but lost a full two stops so I was no better than if I had found a tele-converter ... which I did find later .. a couple of Pentax TCs at NZ$15 each The vendor didn't know what he had found and was selling on auction
Sorry for these two rambles but I have tried quite a few different things over the years

[jcuknz]

Manfred ... Can you do IR photography without doing all the conversion work; sort of. The IR cutoff filter is not perfect and a tiny amount on near IR could still be hitting the sensor. Throw on a visible light cutoff filter and do super-long exposures, and you might get something.

It largely depends on the camera ... my Nikon 5700 and my Canon s20 [ P&S which I started IR with ] work reasonably well but none of my Panasoncs do ... but I still have the 5700 for IR
I am not going to argue but my reaction to focusing was that AF understands IR as a different kind of light and works as normal but I could be mistaken.
This shot was taken 1/2 second f/2.8 according to EXIF off the original file and I simply, as usual, let AF do its job
SOOC just reduced and border added, no sharpening or anything.

The creek behind Canon City railway station as I was filling in time waiting for the train to move

Oh yes ... the test for IR compatibility is to point camera with live view at your TV [whatever] remote and if it shows bright and glowing it is then worth investing in a proper iR filter which are not cheap. I was in a NZ blog group at the time and found three other members who wanted to play at IR and bought a 6"x 6" gel from SRB-Griturn.com and on-sold 3/4s ... otherwise such a filter was beyond, well beyond what I would pay to 'play'.[cost me about $30 against $150 for a filter ] Innitially I used it in my Cokin holder but had lots of problems of light leaks bouncing around during one second exposures in bright sunlight and duely cut it down to fit a filter holder I had..... works better now as you can see

[Manfred M]

Thanks for the information John / Kathy.

I found one or two companies in the USA that did IR conversions, and based my comments on what I remember from the website(s). I agree that the built in IR lets a bit of near IR in (yes I did the remote control test you suggest), but as was mentioned; getting a shot means hauling around a tripod, because so little IR actually gets in and a heavy duty visible light cutoff filter (not cheap) is required. If I recall correctly, conversion costs were running in the $250-$300US range (plus shipping costs).

I did some colour (transparency) and B&W IR photography using film many years ago, so have a bit of an interest, but around here, it is really very much a summer sport. IR photography works fine in the mid-May through late September to early October period. It's a pretty well a waste of time without the leaves on the trees.

John - I suspect you are likely right about the AF working; I can definitely see that contrast detect would work as the measurements would be made by the image sensor. Phase detect, I'm not so sure, as this would still be tuned to the visible spectrum

[Nicks Pics]

Thanks all for the information and experiences. As for infrared, either needing to replace/remove a filter in-camera or use long SS is pretty much the way I understand it. My main point in asking about the adapters is that while there are compact cameras with great zooms available, (those known as superzooms) is it worth buying an adapter for a canon G15 (which has 5x zoom) to increase zoom, to 7-8 x rather than to buy another camera. I personally think the Canon G 15 takes photos of better quality than a superzoom, (based on my own experience) so it would be great if you could extend the zoom reach on that, though realistically there would probably be some IQ loss in the case of using an adapter.

[jcuknz]

My impression is that the G15 as one of the Canon G series would probably take better photos than the Super-zoom which has been designed to work at a much wider range of focal lengths but I do not have personal experience to justify that
But I do wonder as if the difference would be particularly noticeable when the camera is used properly and again my experience comes from a shorter x12 zoom and x10 on MFT. All by Panasonic/Leica which is a plus point.
Also my point repeated that camera lens and adapter need to come from the same stable to be any good though Olympus WCONs and TCONs have good reputations.
I do think that tele and wide adaptors are old tech originally coming from the home movie market where one cannot crop and you get what you shoot and the requirements for quality images is absent by the nature of the beast.
When I was shooting with a x2 Canon P&S the results held up against SLRs on occasions but even in my most enthusiastic moments I was disappointed with results of using adapters.

Finally the idea of increasing of reach from x5 to x7 is really laughable as it is no more than a little bit of cropping does ... you have to go to x10 or 'quarter crop' before you have gained much and things/birds seem to know you have increased your reach and stay further away

I would suggest that your friend uses the G15 for most of his photography and if after birds etc gets a super-zoom for that.

[jcuknz]

Grumpy Diver ... the 'cheap' way to do IR is to do psuedo-IR in Photoshop

[xpatUSA]

The notion that true IR is colorless is theoretically correct. However, unlike John, I prefer those unreal-looking images with faux colors. And then there is the so-called "full spectrum" mode of shooting and endless in-between modes with all kinds of filters on the lens.

For me, the cameras of choice for that kind of work are the Sigma DSLRs (except the first model (SD9) which had the hot mirror epoxied to the sensor). All others, you sinply pop out the so-called dust cover with your thumbnail (SD14 onward) and, voila!, your camera is full-spectrum - awaiting whatever filter or not you care to stick on the lens. Revertable, of course.

I've just bought an SD10 for under $200 to assign permanently to full-spectrum work.

With the Foveon sensor, each of the three layers responds to IR in a ratio of approx 6:2:1 - which can lead to interesting faux coloring and using a program like RawDigger to export the channels separately or as a raw composite can be entertaining.

A full-spectrum test shot of my street (not fall/autumn colors):



Sigma SD1M + 17-50mm kit lens.

[inkista]

We seem to be getting off topic. Mea culpa. Shouldn't have brought IR into things.

... My main point in asking about the adapters is that while there are compact cameras with great zooms available, (those known as superzooms) is it worth buying an adapter for a canon G15 (which has 5x zoom) to increase zoom, to 7-8 x rather than to buy another camera. I personally think the Canon G 15 takes photos of better quality than a superzoom, (based on my own experience) so it would be great if you could extend the zoom reach on that, though realistically there would probably be some IQ loss in the case of using an adapter.

The problem is that teleconverters add glass element(s) to the lens that weren't part of its original design, so there's going to be some performance compromise. Typically, a TC adds a little softness--especially if it's a cheap one. It looks like the good ones come in the $150-$200 price range. And given how aperture works, when you increase the focal length with a TC, you'll also be reducing the maximum aperture of the lens, and probably losing some close focus capability as well. Putting a TC on a camera/lens isn't the same as simply using a longer lens. AF performance can become compromised, because with a smaller maximum aperture, the AF system has less light to detect contrast or phase.

With a G15, it might be worth the image quality compromises, if you need the reach. It's not as if you've got any other choices, really, other than to buy a completely different camera. But chances are good the different camera will perform better at that focal length. A TC is better if you use it as an occasional add-on, rather than think of relying on it as an all-the-time thing. And better if you get a more expensive high-quality one with a lower magnification (e.g., 1.4x vs. 2x). A $25 2x eBay cheapie probably isn't worth it.