Barnard 22 - (CCD + DSLR)

[Uranium235]

Not been sure whether to post this one since its not exactly dark site quality, but I thought I would have a go anyway since I was using the 135mm f2 to fill in the colour.

As predicted... gradients galore in both sets of data, and with the amount of dust about it proved hard to remove the gradients. Also some difficulty in really getting contrast into the dust - a dark site would have helped there rather than an LP'ed town centre location.

Still worthy for the test anyways!

 

30x900 (L) Atik 383L+. Star 71

64x420 (RGB) 1000d, Samyang 135mm f2

 

Thanks for looking!

[PatrickGilliland]

Nice work there for a test, just lacking time and clear skies for the real deep look.  Has all the right elements though and dust looks good so far.

Paddy

[ollypenrice]

Wow, just going for it at all from LP was brave and the result is tremendous. Could you maybe do a version in which you star reduced the red layer? Save that version and apply it only where necessary and as much as necessary on those red stars with a minor issue? I'm knocked out by the quality of this image. 

Olly

[Uranium235]

1 hour ago, ollypenrice said:

Wow, just going for it at all from LP was brave and the result is tremendous. Could you maybe do a version in which you star reduced the red layer? Save that version and apply it only where necessary and as much as necessary on those red stars with a minor issue? I'm knocked out by the quality of this image. 

Olly

Cheers Olly, I spent the best part of 2 days trying to rid myself of those red star halos. The 135mm seems to bloat a little in red @ f2, so im thinking whether there is a way to make the lens focus a little past infinity so I've got some breathing room for adjustment as at the moment - for it to be in focus the lens needs to be focused until it hits the stops.... which doesnt seem quite right (the 50mm always had some play either side of infinity focus). Perhaps that is due to the filter or because its a modded camera.

Whether that means the spacing needs to be increased or reduced, im not quite sure. But I dont have the same problem with the CCD becuase that hits focus a touch before infinity. I'd be grateful if anyone could enlighten me as to how to get that breathing space with the DSLR (adding spacing is not a problem, but subtracting it would prove difficult).

[RichLD]

Hi there, cracking image sir, especially given your LP woes!

If you need to focus beyond the infinity mark/stop on your lens you will need to shorten the register distance (the distance from the lens flange to the sensor).

 This is not going to be possible without adding corrective glass behind the rear lens element or by somehow shaving down the flange of the lens - both obviously undesirable!

I'd search the internet for information on removing the hard infinity stop on your Samyang or on how to adjust the infinity focus point by loosening the focus barrel against the helicoid.

I've done both on older manual focus lenses with great success and reversibility in the past 

HTH

Rich

[Uranium235]

3 hours ago, RichLD said:

Hi there, cracking image sir, especially given your LP woes!

If you need to focus beyond the infinity mark/stop on your lens you will need to shorten the register distance (the distance from the lens flange to the sensor).

 This is not going to be possible without adding corrective glass behind the rear lens element or by somehow shaving down the flange of the lens - both obviously undesirable!

I'd search the internet for information on removing the hard infinity stop on your Samyang or on how to adjust the infinity focus point by loosening the focus barrel against the helicoid.

I've done both on older manual focus lenses with great success and reversibility in the past 

HTH

Rich

Thanks Rich.  I've just had a bit of a brainwave on how to do it without modifying the lens. 

Being as my dslr is full spectrum, the Gary Honis tutorial recommends re-shimming the cmos chip to bring it fractionally closer to the lens. Probably the easiest way to go.

[RichLD]

7 hours ago, Uranium235 said:

Thanks Rich.  I've just had a bit of a brainwave on how to do it without modifying the lens. 

Being as my dslr is full spectrum, the Gary Honis tutorial recommends re-shimming the cmos chip to bring it fractionally closer to the lens. Probably the easiest way to go.

No worries  Yes, that'll certainly do the trick. Gary Honis really is the man, I love watching his tutorials!

Hope you get it sorted and please let us know how you get on!

Rich

[Uranium235]

3 hours ago, RichLD said:

No worries  Yes, that'll certainly do the trick. Gary Honis really is the man, I love watching his tutorials!

Hope you get it sorted and please let us know how you get on!

Rich

Cheers   Im in no hurry at the moment though as with the moon about im back in narrowband mode. Its been a few years since I last had that camera open, so its going to take another careful read of the tutorial. Either that or be really lazy and have it sent off to be re-shimmed.

Im quite certain that its the full spectrum mod that has shifted the infinity focus a bit, and the reason why my 50mm can go past it is because its an AF lens (which needs to go past infinity when finding focus). The 135 is manual focus only, so its infinity is set right at the stops... probably great if your dslr is unmodded or filter replaced (saves time fumbling around in the dark) - but for my camera in its current state, not so suitable.... its good, but it can be better with a bit of tinkering.