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Canon 200D/SL2 Nikon D5300 Comparative Review

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34 replies to this topic

#26 Bretw01

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Posted 21 October 2018 - 11:59 PM

I never “kill green” in my digital images. I don’t know why this is needed by some.

I know the PixInsight NR that can “kill green” existed sine the very early version of PI, when a lot of people (like me) still use film. For reason I don’t understand, film images can often show green grain/noise. So such an algorithm is well justified for film images. But it shouldn’t be the case for DSLR images.

There are no green stars because the stars that emits the strongest in green (like our sun) is defined by our eyes to be white.

I find this interesting. I would assume some try to "kill green" due to the fact that there are two green to one each red and blue filters. I use the SCNR always to reduce the green (even on ZWO ASI183MC Pro), you say you never "kill green" and your images are great. I need to understand this better!


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#27 whwang

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Posted 22 October 2018 - 12:23 AM

In Bayer array, there are twice more green than blue and red. What this means is that the green channel has high S/N and lower noise than the red or blue channels. The brightness difference between RGB should be easily taken care in the initial color balance.

There shouldn’t be anything green that needs to be killed. So, yes, this is interesting.
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#28 JukkaP

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Posted 23 October 2018 - 12:34 PM

In Bayer array, there are twice more green than blue and red. What this means is that the green channel has high S/N and lower noise than the red or blue channels. The brightness difference between RGB should be easily taken care in the initial color balance.

There shouldn’t be anything green that needs to be killed. So, yes, this is interesting.


Might need some fact's? If I mesure the snr in my images usually the red chanel is strongest? Killing the green is personal preferance, as there are not much green in the sky I do get rid of thr green cast.. I use PCC in pixinsight and it leaves green tint to image allways. You are badly going wrong direction in this convercation. Great review and both are good cameras. Still go for nikon as its cheaper and proven to be good. :D
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#29 SteveInNZ

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Posted 23 October 2018 - 02:51 PM

Airglow is mostly green.

 

Steve.



#30 whwang

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Posted 23 October 2018 - 05:40 PM

Might need some fact's? If I mesure the snr in my images usually the red chanel is strongest? Killing the green is personal preferance, as there are not much green in the sky I do get rid of thr green cast.. I use PCC in pixinsight and it leaves green tint to image allways. You are badly going wrong direction in this convercation. Great review and both are good cameras. Still go for nikon as its cheaper and proven to be good. laugh.gif

 

I am not sure I understand you.  The overall green cast can be easily balanced out in the initial color balance, no matter in the background, nebulas, or stars.

 

Here we are talking about faint stars preferentially turned green by D5300's spatial filtering, which is not complained by D5300 users.  A hypothesis to explain the user behavior proposed by Mark is that this green bias on faint stars is unconsciously removed by users in post-processing.  Assuming this is the correct explanation, this process should be very different from the basic color balance.  As you can't use color balance to remove the green bias on faint stars while maintaining the color of the background, bright stars, and other larger celestial objects.  Whatever you apply in the color balance will equally affect all objects in the image.



#31 Bryant H

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Posted 27 November 2018 - 09:36 PM

Hello All,

 

I am really new to AP and purchased a Canon SL2 back in August.  I have been shooting unguided with it for a few months and have had some good results.  My Polar Alignment is still not perfect and since I am not guiding my subs are usually around 60 seconds, but when my tracking is good I see decent results.  Of course I am new, so I don't have a lot to compare it to, but I definitely do not see any banding.  I would like to have my camera tested as well so that we can add more data into this discussion.  Here is a picture I took of the Pinwheel Galaxy from a dark sky location.  The shot is comprised of 27 subs of 60 seconds each at iso 1600.  I probable could have gone as far up as ISO 400, but this was one of my first attempts and my first sub showed a lot of detail without having my histogram too far to the right so I left it alone.  I have shot at ISO 800 and 400 as well with similar results.  I will post some more later.

Attached Thumbnails

  • Pinwheel 9-08-2018-2.jpg
  • Whirlpool 9-08-2018.jpg
  • Ring Nebula 09-11-2018.jpg

Edited by Bryant H, 27 November 2018 - 09:48 PM.

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#32 Michael Covington

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Posted 27 November 2018 - 10:28 PM

Some tests of a 200D are in www.dslrbook.com/Updates2 .  Scroll down to the chart.



#33 sharkmelley

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Posted 28 November 2018 - 03:20 PM

In addition, here are a couple of useful links for calculating sensor parameters:

 

http://www.aicccd.co..._stan_moore.pdf

http://casa.colorado...ts/CCD_Gain.pdf

 

Be aware that if you are using a Nikon camera then it is essential to separate the colour channels and do the calculations on each colour channel independently because each colour channel has a different gain.

 

Mark


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#34 spacescapes

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Posted 10 December 2018 - 10:58 PM

Hi everyone,

 

I was directed here after posting my latest image using a Canon SL2. For reference I'll post here. I have noticed some noise banding, but with stacking/dithering I haven't had any issues in my final images. I don't use any darks/bias since I'm fairly lazy.

This is M45 taken with a Canon SL2 and Skywatcher Esprit 100mm f/5.5 scope. ISO 800. 36 x 5 minute exposures for a total of 3 hours integration time. Dithered every 2 frames. Taken from a dark bortle 2 location. No glaring camera issues that I can't live with, but I'm no perfectionist smile.gif Enjoy and hope this helps with the comparison.

 

Also a higher res version here: https://i.imgur.com/3KwUbMx.jpg

 

A few more images with my SL2 here (first 5 until and including the Lagoon nebula, all ISO 800, bortle 3, under 1 hour integration): https://imgur.com/a/RkWXk

 

The Iris Nebula photo is especially noisy since I only got 3 exposures.

 

Kevin

m45-lrbg-4.jpg


Edited by spacescapes, 10 December 2018 - 11:17 PM.


#35 Michael Covington

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Posted 10 December 2018 - 11:55 PM

Certainly proof that the camera can be used to do good work!




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