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View Full Version here: : Modded Canon 300D & 350D


EzyStyles
11-03-2007, 03:05 AM
Hi Guys,

stupid question, besides the megapixel, any difference between the 300d and 350d for astrophotography use? I much prefer probably a 300d modded than a 350d modded simply because of the smaller FOV. thoughts?
Also, does it require after taking the stock IR filter out, a UV/IR filter? i mean it is a must? I know the UV/IR filter will help the purple star bloat with a refractor how about a newtonian?

thanks.

Adrian-H
11-03-2007, 04:30 AM
The FOV is the same for both of them, the chip is exactly the same crop size its just a difference in MP resolution that makes the 350d photos slightly larger.

The 350D has 8.2MP 3456 x 2304 pixels,
Compared to the 300D at 6.3MP 3073 x 2048 pixels
Which isnt a big difference.

They are both different sensors allso so they probly have different noise patterns, im not to sure about which one has less, but im sure there isnt a huge difference.

gbeal
11-03-2007, 05:23 AM
Eric, as I understand it, with refractive optical systems you will need a UV/IR cut filter, but this doen't have to be on the chip. It can be somewhere within the optical train. Plus you can put a Baader one on later. The $450 one is a real good deal.

Astroman
11-03-2007, 06:37 AM
Doesn't the 300D have more amp glow that the 350D? requiring more processing to remove it? I think I read that somewhere whilst doing research on DSLR's

h0ughy
11-03-2007, 08:58 AM
ok the 300D does have more amp glow than the 350D, but with the russian firmware hack you end up with a nice setup with the 300D when using the mirror up functions.

Now I know why you haven't contacted me Eric, I wish you well on your endeavours.

RB
11-03-2007, 10:05 AM
My understanding is that if you pack more pixels in the same size area, you end up with more noise.
The pixels need to be smaller hence they saturate and spill over into the next well quicker.
Bert is better at explaining these things.


:shrug:

EzyStyles
11-03-2007, 12:00 PM
your spot on the $450 gary ;)

EzyStyles
11-03-2007, 12:02 PM
is that important though the mirror lock up function? I never use mine on the 350d. :shrug:

yess .. i was hesitating to let it go .. mainly because it was my birthday present from my mrs.. sentimental to me.

EzyStyles
11-03-2007, 12:03 PM
i thought if you pack more pixels in the same area that gives it less noise? :shrug: not quite sure

RB
11-03-2007, 12:43 PM
No, larger and less pixels (within reason) yield a better signal to noise ratio.
I'll try and find a link that explains it better.
Don't get me wrong, the 350D is still a great camera.

avandonk
11-03-2007, 01:43 PM
The basic rule is if all else is the same a larger pixel will produce a better signal to noise.
The 350D has in camera noise reduction and mirror lock up. That to me makes it more usable than the 300D. There is nothing wrong with the 300D for astro.

You would have to balance the slightly smaller pixel size against the lack of ICNR and mirror LU.

Basically it depends what you want to do.

It would be good if we could all afford a full frame $15k+ cooled astro CCD camera with all the bells and whistles. The main thing is work out what you can afford and then use it to it's full capability. This then should give you a good idea how far you want to go.

I have said this before most F1 drivers started in go-carts. You just cant get into an F1 without a lot of experience. It is the same with astrophotography!

Start off simple and work your way up. Don't go to the next level until you have mastered the current one. I still have not got to the full capability of my 5DH, so I will keep practicing.

Bert

Garyh
11-03-2007, 03:22 PM
Hi Eric,
I myself went for a 300d over the 350d as I was told there is a slightly better noise/signal ratio even though there is less resolution..
Also went for having the baader filter replacing the canon uv/ir so I could atleast use the camera for normal daytime photography as well (using custom white balance). Pictures still come out pretty good. Also auto focus still works good with a tweak after the mod.
With just a clear window infront of the sensor you will need a uv/ir like the baader filter in your imaging train or you will end up with star bloat from Uv and IR and your images will be verrry red and hard to process.
Hope that helps...:thumbsup:
Cheers

EzyStyles
11-03-2007, 11:40 PM
thanks guys well explained. I can only afford the 300D modded at this stage so I grabbed it on Astromart. It should be arriving next week sometime. I can't wait for the comparison with my current unmodded 350D as well as first light coming out of a modded DSLR.

@gary in regards to the UV/IR filter, even for a newtonian?

gbeal
12-03-2007, 06:53 AM
Eric,
no idea, whatsoever, but the smart money is on putting one in, as it then appeals to a wider range of people and scopes. I can help you with one if you like. Only thing you could do is try a comparison, with and without the filter. Gary

Garyh
12-03-2007, 02:03 PM
Good going Eric, I saw that camera on astromart...
Only drawback that it will be no good for anything else except astroimaging having no filter/glass at all fitted so auto focus lenses won`t focus right and manual focusing with these lenses might not be possible to infinity? (not sure there) You will have to be extra careful sensor cleaning as you will be cleaning the actual chip too..
You can actually get a baader uv/ir filter already cut to fit over the sensor of the 300/350d if you don`t mind operating!! but if not you will need a 2" one for your ED and newt..
Cheers and look forwards to your first posts with your modded camera!
Cheers