Astro Modified DSLR

[Guest VikN46]

Hi all,

 

I have been given the unexpected go ahead my the other half to buy a Astro Modified Canon I have a  question before I take the plunge.

 

Am I right in thinking that a modded camera will allow capture of the red emission wave length of nebulae like Rosette, Orion M42, Veil Nebula, Sadr region etc??? ( HA I think)?

 

Also I am thinking of buying the 600D from Cheap Astrophotography ( I have the 650D unmodded but want to keep it this way) anyone have experience of either the camera or supplier?

 

And lastly will the purchase be worth while?

 

Any other opinions greatly received.

 

Please correct me if I have the wrong end of the stick

 

Many thanks in advance.

 

Vick

 

 

 

 

 

[+RonC]

No Vick, you are right on your asumptions. I don't know about the 600D but my 1000d modded with a CLS filter fitted is great for the targets you mentioned.

 

Cheers

Ron

[Guest VikN46]

Brill thanks Ron,

 

Sounds like it will be a good choice to have in the collection then and just what I want for AP.

 

Thanks

Vick

[red dwalf]

have seen lots of good things said about the supplier, you`ll get alot more of the red with the modified version, 

Colin took a lovely image of the heart nebula with his Modded 1100d at Kelling, came out very nicely, i think he posted a picture of it on the forum somewhere.

not 100% sure that the 600d will be that much of an improvement over the modded 1100d, may be alittle less noisey.

Edited May 25, 2014 by red dwalf

[dawson]

The advantage of the 600D is that it will probably have a newer sensor compared to the 1100D is that it probably has reduced inherent noise, increased "quantum efficiency", may have deeper "wells" so produce greater contrast, but in my opinion the overwhelming advantage is the flip out screen. I don't know what telescope you are using, and how you plan to focus (on a laptop screen or on the cameras live-view screen), but the flip out screen is SO handy, especially when imaging anything above about 60 degrees above the horizon with a refractor or catadioptric, or with a newtonian whenever the camera is underneath (unless you've got rotating rings).

My understanding is yes, the modification enhances detection of the deep reds (including hydrogen alpha) which are mostly, but not exclusively, emitted by [?emission] nebulae. I'm unsure how much the modification helps when imaging galaxies, globular clusters, open clusters, solar system work.

As Ron says, several people use the CLS light pollution filter, and there is a CLS CCD version which i believe is designed to block IR too as in the modification you have no IR filter.

Jd

[red dwalf]

image processor is the same as the 1100d, a DIGIC 4 Image Processor, the screen could be a good idea although i`ve never used my screen preferring to use apt on the computer.

correct about the filter, but if you do have a cls filter all you need is a cheap ir cut filter to screw onto the nosepiece and it`ll do the same job as the cls ccd version.

[dawson]

Rob, I think the DIGIC thing is just the internal processor; i'm pretty sure the two cameras must have different "light" sensors as they are both APS-C and the 1100 is 10 or 12 megapixels and the 600 is 18 megapixels.

Jd

[red dwalf]

with you now James, yes think the 1100d is a 12 megapixel

[dawson]

So the 1100 must have bigger pixels, which in itself can be considered at times to be advantageous.

Jd

[xanthic]

So the 1100 must have bigger pixels, which in itself can be considered at times to be advantageous.

Jd

That'll be balanced out by the QE.

James - do you still have that table comparing them?

[red dwalf]

maybe if you where going to blow the image up to a massive size then it may be but 12 megapixel is still alot, much more for example than a astro ccd camear of the same size chip

[dawson]

Leigh was it this link (which doesn't include the 600D unfortunately):

http://www.sensorgen.info

Jd

[dawson]

Rob i agree, after 10-12 megapixels it probably doesn't make much difference to most of us; i think the higher the megapixels though may suggest the sensor is more modern and as a consequence may have better qualities such as reduced noise which could be beneficial. Also the pixel will be smaller which will alter the arcsexonds to pixel ratio which some people get animated about, but i have no idea if it is that important or not. But i suspect most of this data is out there somewhere, like that link above, just a shame the quantum efficiency and the "read out noise" for the 600d isn't also listed to compare these in more detail.

Jd

[red dwalf]

indeed, lower noise will be a better advantage, and the newer chips should be quieter 

[dawson]

QE for the 600D is 40% apparently. Can't find read noise value yet.

QE for 1100D is 36%.

Not sure if 4% is much or not!!

Jd

[dawson]

And this link, together with the link above [assuming the 600D is very similar to the 550D as this thread suggests], suggests the read noise of the 600d is better at ISO 400 (4.2 vs 6) and at ISO 800 (2.9 vs 4.4) and ISO 1600 (2.4 vs 3).

But if the 1100D is modified, that may be the thing which sways you more.

Jd

[dawson]

The link:

http://forum.orpington-astronomy.org.uk/index.php?topic=8955.0

[Guest VikN46]

Yuck been ill and gutted I had to bring my scope back in Sunday as I felt too rubbish, will have a look at all the information and compare as soon as I feel better, just waiting for antibiotics to kick in. For me I think the 600D is one I will to for it had just about all the features of my 650D (except touch screen) and I love that camera and I am familiar with the 600D as I use it for dental pics at work.

 

CLS Clip filter will be added too.

 

Cheers all.

[Guest AstroOlly]

The advantage of the 600D is that it will probably have a newer sensor compared to the 1100D is that it probably has reduced inherent noise, increased "quantum efficiency", may have deeper "wells" so produce greater contrast, but in my opinion the overwhelming advantage is the flip out screen. I don't know what telescope you are using, and how you plan to focus (on a laptop screen or on the cameras live-view screen), but the flip out screen is SO handy, especially when imaging anything above about 60 degrees above the horizon with a refractor or catadioptric, or with a newtonian whenever the camera is underneath (unless you've got rotating rings).

My understanding is yes, the modification enhances detection of the deep reds (including hydrogen alpha) which are mostly, but not exclusively, emitted by [?emission] nebulae. I'm unsure how much the modification helps when imaging galaxies, globular clusters, open clusters, solar system work.

As Ron says, several people use the CLS light pollution filter, and there is a CLS CCD version which i believe is designed to block IR too as in the modification you have no IR filter.

Jd

You will have an IR filter after the mod, as there are two filters in those cameras and only the front one is removed, the rearmost one is left in, because it has good IR cut, (which is needed for digital imaging) so you only need the normal CLS LP filter, not the CCD version, you will only need that if you have a full spectrum mod and have both filter removed, which I doubt you are doing.

The from filter has IR cut too but a lot more harsh, also this filter blocks a massive portion of the Ha end of the spectrum, hence that is why it is removed.

Hope that helps

Olly

[Guest AstroOlly]

with you now James, yes think the 1100d is a 12 megapixel

You must remember, that these camera are only 12 megapixel if they were mono and had no Bayer matrix on the chip, with that they are actually only a quarter of the stated resolution, a lot of people don't realise that

This is because each pixel has a red, blue and two green filters in front of it, so it actually takes four pixels to create one RGB pixel, hence a quater resolution, and there are two green pixels because our eyes see more green that the other two colours and the idea is for the produced images to look normal to us.

With a mono camera every pixel is used separately so you get full resolution, as there is no colour Bayer matrix filter on the sensor.

Hope that makes sense

Olly

Edited June 2, 2014 by AstroOlly

[red dwalf]

it does Olly and a good point

[Guest VikN46]

My modded Canon 600D has arrived! Cannot wait to try it out now. Keeping everything crossed that the weather forecast is right and stays clear for tomorrow night. Thanks every one for all your help and info!

[red dwalf]

look forward to seeing the results Vicky