Night Photography, Noise, and the Canon 7DII

[Tronhard]

I'm not going to address technique or lenses, just the bodies. One of the things that Canon has worked at of late is dynamic range and noise reduction - the latter being obviously significant in night photography! I don't have all of those bodies but logic suggests that the newer ones should be performing better. There are issues to discuss like are you going for high ISO performance or are you willing to keep the ISO down and accept long exposures? The images you have shown so far are more dusk than night photography, and certainly not Astro photography.

A couple of comments here. If you are doing ASTRO photography, then still consider the Canon 60DA. It's sensor is specially configured to emphasize the reds that are more common out there in the cosmos. Conventional sensors have a matrix of 1R, 1B, 2G because out eyesight favours the green part of the spectrum and our world is (for the time being at least) green. The 60D is not that new but it's a specialist unit.

As far as print size goes, I don't personally think that you are producing what I would call large prints. I produced pin sharp images from a 60D that were on A0 size prints: that's about 33'x46" in imperial numbers. Of course the quality of the lens and a bunch of other operational elements influence that, with a FF sensor with a good lens, technique and PP you should have no issues at that size.

Next, you need to decide if a crop sensor like the 7DII is going to show you enough sky for your purposes. It all depends on how much sky you want to see in your shot... but for wide angle shots a crop sensor is not your friend. Yes, the 7DII has good reviews for NR, but 80D and the 5dIV are getting good reviews and they are both newer technology again. I would recommend checking out a comparison on DPREVIEW between the newer boxes, asking about it on their forum and also doing the same on the Canon forum - I have engaged with it before and there are some night specialist there.

For DPREVIEW comparison see https://www.dpreview.com/products/co...anon_eos5dmkiv

To access the Canon forum log onto your local canon site and look up its forum site.

Thanks, Trev. Great information about the cameras.

As for resolution/output, my goal is for images that are printable and of a fairly good size, at least 12x18 inches. So yes resolution is a key concern for me.

Have you tried these cameras for night photography, or even astrophotography? I am familiar with many recommendations in favor of the 5D models, but I am curious to know how the 7DII compares. What I have heard about it makes it sound really like a great in terms of low-noise output.

[Thlayle]

I'm not going to address technique or lenses, just the bodies. One of the things that Canon has worked at of late is dynamic range and noise reduction - the latter being obviously significant in night photography! I don't have all of those bodies but logic suggests that the newer ones should be performing better. There are issues to discuss like are you going for high ISO performance or are you willing to keep the ISO down and accept long exposures? The images you have shown so far are more dusk than night photography, and certainly not Astro photography.

A couple of comments here. If you are doing ASTRO photography, then still consider the Canon 60DA. It's sensor is specially configured to emphasize the reds that are more common out there in the cosmos. Conventional sensors have a matrix of 1R, 1B, 2G because out eyesight favours the green part of the spectrum and our world is (for the time being at least) green. The 60D is not that new but it's a specialist unit.

As far as print size goes, I don't personally think that you are producing what I would call large prints. I produced pin sharp images from a 60D that were on A0 size prints: that's about 33'x46" in imperial numbers. Of course the quality of the lens and a bunch of other operational elements influence that, with a FF sensor with a good lens, technique and PP you should have no issues at that size.

Next, you need to decide if a crop sensor like the 7DII is going to show you enough sky for your purposes. It all depends on how much sky you want to see in your shot... but for wide angle shots a crop sensor is not your friend. Yes, the 7DII has good reviews for NR, but 80D and the 5dIV are getting good reviews and they are both newer technology again. I would recommend checking out a comparison on DPREVIEW between the newer boxes, asking about it on their forum and also doing the same on the Canon forum - I have engaged with it before and there are some night specialist there.

For DPREVIEW comparison see https://www.dpreview.com/products/co...anon_eos5dmkiv

To access the Canon forum log onto your local canon site and look up its forum site.

Thanks, Trev.

Your comments about getting enough of the sky are true to the mark. That issue is one of the reasons I have been attracted to the full frame line. I have a 14mm prime lens that performs beautifully for the kind of night shots I am doing, but the crop sensor is, as you say, not my friend in that regard.

The 5D line and the 80D both sound like great options (and after all, it was always the 5D series I was most interested in). That's where budget considerations will come in to settle the issue of choosing what I want and what I can afford.

12 x 18 is my starting point for prints. It's that noise issue that is moderating my goals right now.

And, btw, the shared pics are Dan's examples of some very nice nighttime landscape shots. (Thank you, Dan.)

Thanks for the advice. Maybe I can put these ideas together with Richard's note that refurbished equipment can be a great way to keep the budget in check.

Below is an example, greatly downsized, of a night shot that worked fairly well at 12 x18. The noise was greatest in the landscape portion. It is a composited shot. I think I could have done better with the foreground if I had used a lower ISO and longer exposure for that portion of the image.

[DanK]

A couple of additional thoughts:

One reason why noise sometimes appears in night photos is that people often expose them to look dark. When there isn't a reason to do that, that's a mistake. If you lengthen the exposure and expose to the right, then darken in post, noise isn't generally an issue at low ISOs.

However, astrophotography adds another wrinkle. In what I do, I can usually keep the ISO low and lengthen exposure to get the exposure I want. If stars form trails, that's fine by me. In a shot like this last one, if you want to keep the stars as points rather than streaks, then a long exposure won't work (although the shorter the lens, the longer the exposure you can use). So in those cases, higher ISOs may be necessary, and the noise characteristics of the camera will be more important than they usually are for me.

Re the effectiveness of long-exposure noise reduction: it is virtually useless for the more or less random noise caused by high ISOs or ETTL. In my experience, however, it works very well for the fixed-location noise that arises with really long exposures.

[Donald]

A couple of additional thoughts:

One reason why noise sometimes appears in night photos is that people often expose them to look dark. When there isn't a reason to do that, that's a mistake. If you lengthen the exposure and expose to the right, then darken in post, noise isn't generally an issue at low ISOs.

That is the most important statement of the lot.

Get the exposure right, and noise is very seldom a problem.

[rpcrowe]

Thanks,Richard. I will have to try Dfine. I have not had a lot of luck with the in-camera noise reduction, at least for many of the things I am attempting.

In as much as the complete NIK Package is a free download, a person would have absolutely nothing to lose in trying Dfine or any of the other NIK programs...

[Thlayle]

A couple of additional thoughts:

One reason why noise sometimes appears in night photos is that people often expose them to look dark. When there isn't a reason to do that, that's a mistake. If you lengthen the exposure and expose to the right, then darken in post, noise isn't generally an issue at low ISOs.

However, astrophotography adds another wrinkle. In what I do, I can usually keep the ISO low and lengthen exposure to get the exposure I want. If stars form trails, that's fine by me. In a shot like this last one, if you want to keep the stars as points rather than streaks, then a long exposure won't work (although the shorter the lens, the longer the exposure you can use). So in those cases, higher ISOs may be necessary, and the noise characteristics of the camera will be more important than they usually are for me.

Re the effectiveness of long-exposure noise reduction: it is virtually useless for the more or less random noise caused by high ISOs or ETTL. In my experience, however, it works very well for the fixed-location noise that arises with really long exposures.

Thanks, Dan - and Donald.

A confession in this case: this is a composite shot and the foreground portion WAS indeed lighter than needed in this situation. I wanted to use the shot of the barn, which happened to face the wrong way for my purpose (the northern most end of the milky way being the less interesting). So, yes I forced it this situation, partially in post-processing. Therein lies much my problem in this image.

As for the longer exposure times, Dan, I occasionally like star trail shots but mostly I am going for the stars and not the trails, which limits me to higher ISOs. Even with the best equipment, star trails begin showing up anywhere from 20 to 30 seconds, depending on the focal length and the direction of the shot.

And Donald - getting the exposure right - I get that. With 20-30 seconds exposure and high ISO (necessary even with full frame cameras and fast lenses), noise is the constant battle to overcome. Hence my interest in full frames or some other Canon model that will perform better on that factor.

Thanks so much to everyone.

Richard, I have the Nik collection installed & am going to try out Dfine as soon as I get a chance.

-Randy

[proseak]

Very nice pic- I'm jealous

There's a very great deal you can do with different shooting and processing techniques, and most of these involve stacking very similar images. Deep Sky Stacker is free here -

http://deepskystacker.free.fr/english/index.html

There are a lot of tuts & tips.

I use a T3i, and find it quite easy to produce very low noise images using this.

[William W]

The Lens which used is related to your question:

For “night skies”, there are basically two options (for the depiction of the sky), either you want star trails or you do not want star trails.

If you do not want Star Trails, then you want to be near the shorter end of EXPOSURE TIME: ergo access to a faster aperture means the capacity to use a lower ISO.

If you do want Star Trails, then, Exposure Time becomes the priority in regard to the size and/or shape of those Star Trails. However it is worthwhile noting that once choosing the required Exposure Time for the desired Star Trail the access to fast Lens Speed (fast Aperture) also allows for the selection of a lower ISO.

The same logic applies to making Long Exposure Images with no stars – the faster the Aperture the lower the ISO for any given Shutter Speed selected.

Add to the consideration of Lens Speed a (general) comparison of optics and geometry of a Prime Lens compared to a Zoom Lens.

Then consider the widest FoV from the fastest W/A lens available for Canon . . .

Many of the reasons why a 135 Format Camera (aka “full Frame” camera) and the EF 24F/1.4L MkII USM are the favoured combination for this type of work.

WW

[Thlayle]

The Lens which used is related to your question:

For “night skies”, there are basically two options (for the depiction of the sky), either you want star trails or you do not want star trails.

If you do not want Star Trails, then you want to be near the shorter end of EXPOSURE TIME: ergo access to a faster aperture means the capacity to use a lower ISO.

If you do want Star Trails, then, Exposure Time becomes the priority in regard to the size and/or shape of those Star Trails. However it is worthwhile noting that once choosing the required Exposure Time for the desired Star Trail the access to fast Lens Speed (fast Aperture) also allows for the selection of a lower ISO.

The same logic applies to making Long Exposure Images with no stars – the faster the Aperture the lower the ISO for any given Shutter Speed selected.

Add to the consideration of Lens Speed a (general) comparison of optics and geometry of a Prime Lens compared to a Zoom Lens.

Then consider the widest FoV from the fastest W/A lens available for Canon . . .

Many of the reasons why a 135 Format Camera (aka “full Frame” camera) and the EF 24F/1.4L MkII USM are the favoured combination for this type of work.

WW

Thanks, Bill. Well said and sums up why I am drawn to the full frames. Maybe I can look in the direction of a refurbished camera, as Richard suggested.

[Thlayle]

Very nice pic- I'm jealous

There's a very great deal you can do with different shooting and processing techniques, and most of these involve stacking very similar images. Deep Sky Stacker is free here -

http://deepskystacker.free.fr/english/index.html

There are a lot of tuts & tips.

I use a T3i, and find it quite easy to produce very low noise images using this.

Thanks, Peter, both for the tip and the comment on the picture. I will have to check out Deep Sky Stacker. I used another program called StarStax that worked beautifully for star trails. Worth checking out if you haven't tried it. It is amazingly fast at combining images for star trails.

[proseak]

For star trails, I use Photoshop; load Files as Layers>Smart Object>Stack Mode>Maximum.

There can be gaps in the trails though