Rawtherapee

[RonH]

Camera RAW processing for Panasonic TZ70 RW2 files.

I currently use Silkypix but am considering Rawtherapee which opens the RW2 files associated with this camera. However when opening RW2 shot on wide angle, this effect shows in Rawtherapee, Silkypix has resolved this effect at import of the file.

How do I resolve the edge distortion using Rawtherapee?

Cheers Ron

[Shadowman]

Does RawTherapee have a lens distortion correction function?

[RonH]

Hei John & thanks for your response.
I am sure that it does have this correction but I am very new to the programme. I will try to register on their forum and post this question there. But if there is an answer from CiC then most welcome
Cheers Ron

[Shadowman]

Hei John & thanks for your response.
I am sure that it does have this correction but I am very new to the programme. I will try to register on their forum and post this question there. But if there is an answer from CiC then most welcome
Cheers Ron

It's listed in the manual, always a good place to start.

https://rawtherapee.googlecode.com/h...eManual_en.pdf

[RonH]

It's listed in the manual, always a good place to start.

https://rawtherapee.googlecode.com/h...eManual_en.pdf

Saw that but ain't managed to work it out yet! Age you know!
Ron

[xpatUSA]

Saw that but ain't managed to work it out yet! Age you know!
Ron

My prime computer is in the shop being fixed and no RawTherapee on this one, so from memory (mine): in RawTherapee, it does indeed have the standard image correction options, trapezoidal, barrel/pincushion and also vignetting.

Not sure but I think it can also use lens profiles, for what that's worth.

[RonH]

Thanks Ted ... just managed to gain contact in the RawTherapee forum. They requested I upload the RW2 file which I have done. Seems that RW2 lens profiles are important ... perhaps this is only to do with the settings but no doubt an answer will be forthcoming. Will post it here once I have a solution.
Cheers Ron

[Manfred M]

Ron - something that happens with the mFT cameras is that they embed lens correction data in the raw data. This needs to be interpreted by the raw converter and applied during the conversion process, otherwise you get the results you are showing.

These cameras use a combination of hardware (lens) and software correction to create images. I seem to remember that Leica would not allow Panasonic to use the Leica branding on the mFT lenses if lens correction was used during the early days of their cooperation. I understand that this may no longer be the case.

Silky Pic aside, I can confirm that Adobe Camera Raw (and Lightroom), DxO Optics Pro and Capture One do have this functionality built in. It seems that RawTherapee does not.

[xpatUSA]

Thanks Ted ... just managed to gain contact in the RawTherapee forum. They requested I upload the RW2 file which I have done. Seems that RW2 lens profiles are important ... perhaps this is only to do with the settings but no doubt an answer will be forthcoming. Will post it here once I have a solution.
Cheers Ron

Also, I vaguely recall that Panasonic OOC JPEGS are lens-corrected but the RW2 raw [image data] is not. I had a DMC-G1and a GH1 micro four-thirds for a while and there was no sign of any correction in raw images opened in FastStone viewer, IIRC.

Good luck with the quest.

[RonH]

Thanks for all your inputs. I have the answer from RawTherapee as follows:

The problem in your image is not vignetting, but the lens hood (or plastic from the camera's body) going into the frame. Camera manufacturers hide this problem at the same time as they correct lens distortion.
In this case even clicking the auto-distortion correction button doesn't hide all of the lens hood, so you additionally need to crop the image. It's not a fault or weakness of RawTherapee - the lens hood is there and you cannot fix that, you need to crop it - if you examine the JPEG from your camera or the JPEG embedded in your raw file, you will see that that is exactly what your camera does - crops the image.

Fortunately I rarely use the widest angle and if I do then I can crop ... or simply shoot in jpg only and as you say let the camera make the crop. Rather disappointing that none of the many camera reviews I studied about TZ70 prior to purchase pointed this out.
Guess who is going to 'debate' this with Panasonic
Cheers Ron

[Donald]

Guess who is going to 'debate' this with Panasonic
Cheers Ron

Let us know what happens, Ron. First reaction is that it seems daft that they put a camera out there onto the market with this as a known problem. More particularly, as you imply, they don't tell anyone about it.

[davidedric]

I've never really thought about this before, but I wonder how often this is a hidden problem. I don't know anything about the TZ70 other than it's a 30x zoom.

With an ilc camera, you would have a very different shaped lens hood for a 15mm as compared with a 450mm lens. Must be quite a challenge to design a lens and hood that are effective across a similar range.

Dave

[lukaswerth]

Perhaps I am slow on the uptake, but it seems to me I am missing something here. Do you want the black shadows on the edges removed? If yes, then I think in this particular photo you posted, just this edge distortion is what makes the picture somewhat attractive to me.
Haven't worked with Rawtherapee for quite some time, but it used to be a pretty good editor for someone who doesn't want to /cannot use Lightroom/Photoshop. Not as systematic or self-explaining as commercial programs, but quite effective.

Lukas

[RonH]

A bit more information just advised to me ...

Normally you do not see this behaviour, even if you shoot Raw, with the commercial Raw converters like Lightroom. They automatically correct the vignetting (by distortion correction and cropping) based on the manufacturer's parameters when they open the Raw file, it cannot even be disabled. Raw Therapee shows you the plain Raw data in all its "glory" . My Canon PowerShot G7 X looks similar at wide angle, by the way.

The really bad thing about this for camera JPGs (and probably also Raw converters that do this automagically)is that the cropped image is blown up to the nominal Megapixel count of the camera. For example my G7 X files at full wide angle have only about 14 MP left after distortion correction and cropping in RT. However, the in-camera JPG processsing outputs these files as 20 MP JPGs so people don't notice the trickery. As a side effect, the picture looks softer viewed at 100%, especially in the corners, and it is this what usually gets noticed in the camera reviews.

Seems that it is 'common policy' ... I might drop a comment to Panasonic to get a reaction From a usage point of view I can easily work around but I wonder what the real 'wide angle' is of this particular lens.
The outline 'shadow' is in fact the plastic around the lens! However, I am overall impressed with this little camera and don't plan to return it ... I still have my DSLR for any 'specials'.

[rachel]

Thanks for all your inputs. I have the answer from RawTherapee as follows:

The problem in your image is not vignetting, but the lens hood (or plastic from the camera's body) going into the frame. Camera manufacturers hide this problem at the same time as they correct lens distortion.
In this case even clicking the auto-distortion correction button doesn't hide all of the lens hood, so you additionally need to crop the image. It's not a fault or weakness of RawTherapee - the lens hood is there and you cannot fix that, you need to crop it - if you examine the JPEG from your camera or the JPEG embedded in your raw file, you will see that that is exactly what your camera does - crops the image.

This is interesting. I've very little experience with RAW processing but started to play with Photivo a couple of months back. When comparing my processed versions with the in-camera jpeg, I first thought there was an issue with the size of the image being output by Photivo, until I realised that actually the jpeg was indeed a cropped version of the RAW file.

Is jpeg cropping standard then and if so, is the lens hood the reason?

I didn't notice any lens hood effects but I don't know if I was using it at the time. I may try again, with hood on, just to see.

[RonH]

Hei Rachel,

I am no expert (as you will have gathered from this thread) but, learning fast, I would say that if your jpg is a slightly cropped version of your RAW file it is due to the lens at wide angles capturing the plastic surround as the shot is taken. Some RAW processing programmes have 'co-operation' with the camera manufacturers such that you never see this effect when you open the RAW file in their programme ... all you see is the RAW already cropped exactly as the jpg. RawTherapee shows 'all' ... the other RAW file converter I have been using ... Silkypix ... does not show the fringing caused by the plastic surrounding the lens.

Cheers Ron

[rachel]

That's even more interesting, maybe that's why I had never noticed it previously when playing with darktable in the past.

[Shadowman]

I didn't realize we were talking about a point and shoot camera, I only mention the type because the camera has the same design as most point and shoot cameras and I've never seen this type of distortion in any I've owned; there's no detachable lens hood just the square face which covers the lens barrel. The comment below was from a user of the Panasonic TZ70 model you own and mentions the distortion.


Don't buy - you will be disappointed

By Manu Budhrani, Nov 17, 2015


I have owned a number of Panasonic cameras over the years and this by far is one of their worst offerings. The biggest flaw on this camera is that the flash sits under the shutter release button and inadvertently your finger will cover the flash every time you use the camera. I have taken so many photos over the past couple of months that have dark spots because of this. Then, because of the superzoom feature, approx 10% to 15% of the image is skewed at the edges, all around. What this basically means is that if you have a subject's head or some other feature like a building at the edge of the image, it will be distorted and not appear to look normal. I wish I could return the camera, but it is now past the time that I can return it, so I am stuck.

[rachel]

Off topic a bit but coincidentally I have a Panasonic travel zoom as well and I really don't rate it. It replaced a beloved Fuji one (actually a series of Fujis over about 10-12 years, from F10, F30, F80, to F660). I haven't noticed the distorsion so much as the general lack of quality in the image and even small zooms. It's also very slow to start up or to change setting. I have a new Fuji one on order and am very excited to get my hands on it. It'll be waiting for me when I get back to the uk at Christmas.

[Shadowman]

Off topic a bit but coincidentally I have a Panasonic travel zoom as well and I really don't rate it. It replaced a beloved Fuji one (actually a series of Fujis over about 10-12 years, from F10, F30, F80, to F660). I haven't noticed the distorsion so much as the general lack of quality in the image and even small zooms. It's also very slow to start up or to change setting. I have a new Fuji one on order and am very excited to get my hands on it. It'll be waiting for me when I get back to the uk at Christmas.

I own a Nikon S220 that I purchased six years ago, it was fast and sharp when I first used it but seemed to get sluggish as time went on; it's rarely used at all now.