Disadvantages of modifying a DSLR

[smr]

Hi all,

I'm really wondering whether to buy an astro modded DSLR now as I was going to buy a dedicated astro camera but the cheapest if I was going that route would  be the 294MC Pro and that's around £1k, and that's been put on hold for a bit with the current situation.

But I am so frustrated at not being able to image Ha objects that I'm wondering whether to buy a cheap DSLR for £200 and mod it myself. I think I should be ok with that as I can disassemble a laptop completely and put it back together so it's basically not much different to that.

So if I were to buy a Canon 700D for that kind of price, and mod it myself, presumably that just means following one of the many guides on the Internet and removing the IR filter? And that's the mod done? 

Are there any disadvantages to this as I have heard that star bloat can be a problem when a DSLR has been modified ?

I'm not bothered about the autofocus not working as to be frank, I have never used autofocus in two and half years of doing AP.

Any other disadvantages ?

And also if I do go ahead and remove the IR filter do I need to then buy a filter for the DSLR to be able to use it properly for AP ( I think I've read that you need a UV/IR filter or something )

 

Many thanks for any advice!

[Dr_Ju_ju]

A DSLR, is NOTHING like a Laptop, it is a much more confined space, with smaller connectors, smaller screws, finer wires etc. all requiring precision tools...  then when you've got it apart, removing the stock filters is very delicate work.

 

[steppenwolf]

14 minutes ago, smr said:

Are there any disadvantages to this as I have heard that star bloat can be a problem when a DSLR has been modified ?

 

14 minutes ago, smr said:

And also if I do go ahead and remove the IR filter do I need to then buy a filter for the DSLR to be able to use it properly for AP ( I think I've read that you need a UV/IR filter or something )

You will need an external IR reject filter as without one you will get star bloat and other issues! If you do go ahead, I wish you luck and the only advice I can give you is to work in the cleanest air conditions that you can and take it slowly!

[smr]

3 minutes ago, steppenwolf said:

 

You will need an external IR reject filter as without one you will get star bloat and other issues! If you do go ahead, I wish you luck and the only advice I can give you is to work in the cleanest air conditions that you can and take it slowly!

Thanks, so if I wanted to add a Ha filter at some point how could I go about that, clip in Ha and an IR in the optical train ?

[Wyvernp]

4 minutes ago, smr said:

Thanks, so if I wanted to add a Ha filter at some point how could I go about that, clip in Ha and an IR in the optical train ?

The Ha filter will only let through a certain nm range of light so that should cut the IR out anyway. Here's the graph for baader 7m Ha filters

There is a bit of leakage at the end but that "should" be very minor as I think most CMOS sensors are not very sensitive to these wavelengths

Edited April 14, 2020 by Wyvernp

[michael8554]

A 700D has a spring loaded sensor, and getting the sensor back in place without tilt is difficult.

I suggest a 450D, 500D, or 550D, that have shimmed sensors.

Michael

 

[smr]

On 15/04/2020 at 01:00, michael8554 said:

A 700D has a spring loaded sensor, and getting the sensor back in place without tilt is difficult.

I suggest a 450D, 500D, or 550D, that have shimmed sensors.

Michael

 

Never heard of that one !

[michael8554]

1 hour ago, smr said:

Never heard of that one !

Which one .....? 

Michael