A problem I've been having for a long time is a serious lack of reds in my images. I've learned to accept it as there are a lot of beautiful Nebs out there that aren't only red.
Two nights ago I tried to capture the Cone nebula. 2 1/2 hours of data and still very faint reds. Last week, Rosette gave me the same issue. Its time to accept that need to do something about it. Astro modding my 5d seemed less desirable than pulling apart my old 350d, purely given the value the two cameras untouched.
Out of interest, I thought I'd test the cameras on the same object at the same time to give me a good base line comparison. And why not throw my fiances new 200d in the mix too ( i must say I'm a big fan of live view for focusing ).
The results are quite stark between the 3.
The region is Eta Carinea ( It's bright and has a lot of red cloud and can be imaged from my Bertole 7-8 skies )
All 3 are sets of the best 8 subs x 30 Seconds @ ISO 800
The only post processing that has been done is 100% saturation of the red channel.
Canon DSLRs vary hugely in their Ha sensitivity. My old 1100D was better
than my 600D is. Unfortunately it didn't have the articulated screen which
my ancient neck finds invaluable. Some other brands have models which are
more Ha sensitive than Canon.
raymo
Then I'd say f/10 is a bigger part of the problem rather than your camera. Compare the cameras at f/5 or f/6 and see how they look.
Given that the 3 imags below are all captured using the same equipment and the 350 shows more red sensitivity than both the 5 and the 200, I'm not sure how using a faster scope will change the ability of the camera ? For sure a fast scope will collect more light and also being at a dark site will improve the Ha capture but surely apples for apples the 350 will still out perform the other two cameras ?
If you have an android tablet by any chance you can use a USB On the go cable & DSLR controller app to use your 1100d again & avoid the neck issues. That's what I am doing now & it works really well...
Cable was about $8 from Office Works, app was around $10 from memory.. I'm using a 10.5" Samsung Galaxy tablet (not that new or powerful) & it makes using it a breeze with a much bigger screen to boot...
Quote:
Originally Posted by raymo
Canon DSLRs vary hugely in their Ha sensitivity. My old 1100D was better
than my 600D is. Unfortunately it didn't have the articulated screen which
my ancient neck finds invaluable. Some other brands have models which are
more Ha sensitive than Canon.
raymo
Yes you've got a comparison, but I think you're being too hard on all of the dslr's with 30 second subs at f/10.
Don't get me wrong Tony. I wasn't actually expecting anything of use out of those subs. Periodic clouds were coming through all night and 30s was just a short sub length that I chose that I was confident I could do between them but also long enough that I would expect to capture some red. The test was purely a Ha sensitivity comparison test.
For the record, I've only just in the last month moved to an EQ mount. All of my early imaging was with the C5 on an Alt Az mount that could only be relied on for 22s subs. I've been a lot harder on my poor DSLRs than this
I'm sorry if I haven't articulated it well but the test is for Ha sensitivity of the camera sensor in each camera. It's not processing or longer subs to extract more red. i am well aware of everything else that is involved in producing Astro images. This thread is purely showing the differences between the Ha sensitivity of each of my unmoddified Canon DSLR cameras.
Thanks Glen. Now that I've got a good base line test to know the 350 is the best with the reds in stock form, I've done a proper set of subs on it which I'll process tonight to make sure I'm happy with the image quality. If everything goes well, I think astro modding it will be the next step. Thanks for the link
I don't know if this is actually a useful test if you are going to mod. Ha sensitivity is down to the IR filter which gets removed in modding. So you really need to remove the filter on all three cameras then do the test again. You've only tested which is most sensivity in stock form and thats it, so you know which is best to use in stock form NOT which is best to mod.
I don't know if this is actually a useful test if you are going to mod. Ha sensitivity is down to the IR filter which gets removed in modding. So you really need to remove the filter on all three cameras then do the test again. You've only tested which is most sensivity in stock form and thats it, so you know which is best to use in stock form NOT which is best to mod.
You're right Sil. I had a feeling someone was going to point that out when I read what I wrote in my last post. A better way to articulate it would have been I'll use the 350 in it's stock form because it's the best performer stock and if I want more Ha again then the next step is to mod it. The run of subs I did last night with the 350 is to see if I'm happy with the image that particular camera gives me. Not just Ha sensitivity wise but also the quality of the actual image. If I do want more Ha but the image is really pixilated or has hot sensor issues then it will be pointless modding that one and I maybe need to look at a different camera all together.
I think what is kind of being missed and seems to get missed a lot is that my posting of this test ( although I had my own personal reasons for doing it ) was to share information. If someone was looking into getting into astrophotography and had a friend selling one of these cameras cheap or had one sitting in the cupboard and wanted to know if it was a good one to use, reading this post might give them some insight as to what to expect from them. Yes I did the test for my own benefit but I'm not too selfish to share my findings to help others. Sometimes the dissection of people's work on this site can be a little disheartening. I thought we were all in it together to help broaden the interest level in this amazing hobby.
The Nikon D5300/5600 is the default recommendation for an affordable, low noise dslr. There are other similar options from Sony and Fuji.
My Nikon D5600 is dramatically less noisy than my previous Canon 600D. If you want more red sensitivity it still needs to be modded though.
Goodguys sometimes have 20% off on ebay or ebay itself has sometimes 10% off.
Those two Nikons, which both use the same sensor, are very good with the red end as well for some reason. Just make sure you turn off all the extra software features you don't need but which generate heat. For example, you don't need in camera dark processing.
