Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

How to fit a LP filter with a SW reducer/flattener

Spikey

By Spikey
in Discussions - Cameras

Recommended Posts

Merlin66

Merlin66

Posted
Posted

help me here guys...

I don't have the reducer/flattener you're using but exactly which threads does it have at the front...and the rear....I/we seem to be saying M48 filter thread??

If that's the case you must have a "special adaptor" - the M54>M48?? to fit the reducer/ flattener to the focus tube???

If that's the case why doesn't the M48 filter just fit at the FRONT of the flattener????

The the distance at the back/rear doesn't matter....

help me....

Link to comment
Share on other sites
  • Replies 98
  • Created
  • Last Reply
Sp@ce_d

Sp@ce_d

Posted
Posted
help me here guys...

I don't have the reducer/flattener you're using but exactly which threads does it have at the front...and the rear....I/we seem to be saying M48 filter thread??

If that's the case you must have a "special adaptor" - the M54>M48?? to fit the reducer/ flattener to the focus tube???

If that's the case why doesn't the M48 filter just fit at the FRONT of the flattener????

The the distance at the back/rear doesn't matter....

help me....

This is it attached to focuser with the LP filter on the back

post-23839-133877680253_thumb.jpg

Link to comment
Share on other sites
martin_h

martin_h

Posted
Posted

Well I give up then, there is no way to fit a filter in the chain and keep the correct spacing.

For DSLR users the best way would to fit a clip in filter, that would give the reducer-T mount- camera spacing required, as it was designed for that.

Link to comment
Share on other sites
Sp@ce_d

Sp@ce_d

Posted
Posted
Well I give up then, there is no way to fit a filter in the chain and keep the correct spacing.

For DSLR users the best way would to fit a clip in filter, that would give the reducer-T mount- camera spacing required, as it was designed for that.

Yes, the clip in will work. However, In my case it seems false economy to buy clip ins as I intend to go CCD eventually. Also means removing the camera to change the filter. I can't believe no one else has had this problem.. surely this is one of the most widely used combinations of kit?

Link to comment
Share on other sites
martin_h

martin_h

Posted
Posted

Plan "C" get rid of the Reducer/Flattener, If I can't get the spacing right its not going to reduce or flatten correctly, and If I'm going to end up with eggy stars at the edge I might as well not have the ruddy thing in there in the first place.

Link to comment
Share on other sites
martin_h

martin_h

Posted
Posted

I can do it with the OSC camera - oodles of room there, 15mm from front face of CCD to chip face so that leaves 40mm to play with---no problem there.

But with the mono and filterwheel there I'm at 55mm with no LPR filter and nowhere to put it. The nose piece was a good idea, but with the weight of all the gubbins hanging on it and just pinched with two thumb screws it sagged and I could move it with a finger under it, not ideal!

Link to comment
Share on other sites
Spikey

Spikey

Posted
  • Author
Posted

No, I don't believe so. The reducer is fitted on the M48 and onto the DSLR exactly as it should be with nothing in-between so that spacing should be as intended. The LP filter is now sitting on the adapter 'in front' of this arrangement. I'll bung a pic up when I get chance.

Spikey,

Isn't that the same arrangement as Martin??? Where he had toooo much slop???

Link to comment
Share on other sites
Sp@ce_d

Sp@ce_d

Posted
Posted

Hmm so the whole thing sits inside the tube. I'm still wary of any play though. If you can notice it surely the sensor won't be sitting square to the tube.

I can't believe there isn't an M48 to 2" whatever the thread is on the SW focuser though.

TS seem to have loads of adapters Adapter - Teleskop-Express: Astro-Shop + Fotografie + Naturbeobachtung but I don't know what the SW focuser thread is called.. anyone know?

Link to comment
Share on other sites
Black Knight

Black Knight

Posted
Posted
Hmm so the whole thing sits inside the tube. I'm still wary of any play though. If you can notice it surely the sensor won't be sitting square to the tube.

I can't believe there isn't an M48 to 2" whatever the thread is on the SW focuser though.

TS seem to have loads of adapters Adapter - Teleskop-Express: Astro-Shop + Fotografie + Naturbeobachtung but I don't know what the SW focuser thread is called.. anyone know?

No idea, but it's way bigger than 2" though.

Link to comment
Share on other sites
Sp@ce_d

Sp@ce_d

Posted
Posted

So far the Flo adapter looks like the only option then, aside from clip-in's if you're a canon user. One thing I'm now concerned about is how to choose the correct CCD & FW to match when I come to move on from the DSLR. Which is looking even more complicated than I had bargained for!

Am I correct in thinking the optimal distance ie. 55mm in this case, is for the full illumination of the sensor. Therefore different sensor sizes require different distances?

Link to comment
Share on other sites
martin_h

martin_h

Posted
Posted
So far the Flo adapter looks like the only option then, aside from clip-in's if you're a canon user. One thing I'm now concerned about is how to choose the correct CCD & FW to match when I come to move on from the DSLR. Which is looking even more complicated than I had bargained for!

Am I correct in thinking the optimal distance ie. 55mm in this case, is for the full illumination of the sensor. Therefore different sensor sizes require different distances?

No. The full frame is optimal, but a smaller sensor will just "look" at a smaller view towards the centre.

If you are going to use a very small sensor the reducer/flattener might not even needed, apart for reduction.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.