Light pollution filter for a t-ring?

[DaveGarland]

Can anyone tell me what light pollution filter I can get to fit a Cannon 1100d T-ring adapter? What thread size and where can I order one? I have a 1.25 inch filter but this is just too small.

Advice please!

Dave.

[Ewan]

Hi david, First Light Optics :-), Rother Valley Optics Both are reliable & in UK & Teleskop Service is abroad but choice is massive , very good web site.

I bought an 1.25" LP filter for mine but i swithced to using a 2" imaging system, much better but i'm not sure what goes with your scope, someone may correct me but best bet is CLS Clip Filter heres a link from an SGL topic about such an item, it's a bit dearer @ £99.00 but probably well worth it, i am saving for one myself, i would let you have mine but i'm going to be using it with my Toucam Pro sorry Dave, hope this helps but im sure someone with a lot more knowledge than me may shed some light on what i have posted.

All the best Dave & clear skies :-)

[Ewan]

Just checked Dave FLO has this one if it's what your looking for http://www.firstlightoptics.com/light-pollution-reduction-imaging/skywatcher-light-pollution-filter.html

[DaveGarland]

Ewen, that's the one I have. I want one to fit the thread on a T-ring adapter for a cannon 1100d. It seems to be about 1.5 inches!

[DaveGarland]

Er, is it that I've been a bit dim and need one of these?

http://www.scopesnskies.com/prod/antares/slr-camera-adaptor/t-thread/nosepiece.html

Will this position the camera a little distant for focusing on a 200p? At present I remove the 1.25 adaptor to reveal a thread that the t-adaptor fits onto. This places it closer to the scope than it would be using the above adaptor.

Dave.

[Ewan]

Hi Dave, sorry about that must have mis read your post i guess, so do you want the LP filter IN the T Ring connector ? then what ? the 1.25" T Adapter ? to be honest i have not even thought about that setup (not sure you can) thats why i suggested the CLS Clip filter.

Sorry i can't help anymore Dave more info might help.

[DaveGarland]

Yup! That's where I thought I could fit a filter. I figured that was what that thread was for. Clearly I'm new to all this But anyway I can use my present filter would be cool.

[Ewan]

Dave im not sure if it helps with your 'problem' (if you have one) vignetting, smaller circular bright image with dark corners ? that filter you have will thread into the top of the T Adapter as well as the bottom placing it nearer the sensor by about 35mm Depends what length adapeter you have i guess :-), i have not seen anyone put a filter where you are saying but im not an expert myself either, sorry i can't help more & maybe someone else will cast some light on this for you.

[ronaldo999]

The CLS clip filter is a much better, although more expensive, option. Its simple to fit and gives excellent results.

[RikM]

I am not sure what (if any) filters would screw into the T-ring

I use a 2" SkyWatcher light pollution filter screwed onto the focuser end of the T adaptor nose piece.

[russellhq]

I'll try and describe how I use my 1.25" filers with my Canon 1100D.

1. Remove the 1.25" adapter and the plate it's screwed into from the telescope focuser on my 150P.

2. Remove the 1.25" adapter from the plate and screw it in from the other side

3. Take the barrel from an eyepiece and screw in your filter

4. Pop the barrel into the 1.25" adapter and use 5mm long M3 grub screws to secure in place

6. Connect this final assembly to the Canon T-Ring adapter and screw onto camera,

7. Pop the whole lot onto the telescope and hey presto you've got a 1.25" filter for your camera

I do this with mt Skywatcher 150P, Canon 1100D and Bader filter.

[jimmyjamjoejoe]

I'll try and describe how I use my 1.25" filers with my Canon 1100D.

1. Remove the 1.25" adapter and the plate it's screwed into from the telescope focuser on my 150P.

2. Remove the 1.25" adapter from the plate and screw it in from the other side

3. Take the barrel from an eyepiece and screw in your filter

4. Pop the barrel into the 1.25" adapter and use 5mm long M3 grub screws to secure in place

6. Connect this final assembly to the Canon T-Ring adapter and screw onto camera,

7. Pop the whole lot onto the telescope and hey presto you've got a 1.25" filter for your camera

I do this with mt Skywatcher 150P, Canon 1100D and Bader filter.

Took me a while, but i figured this out the other day

I cant acheive focus with a normal t-adapter, the one built into the focuser has a much lower profile.

[Ewan]

Like above i am also looking at the CLS Clip filter as from what i have been advised / read it is better to have the filter as close to the sensor as possible, just cost holding me back but i have some children i could sell , i was struggling to remember if i saw a filter that went into the T Ring itself & a google bought up nothing but the usual.

[russellhq]

I took some photos to show what I mean. By adding a second barrel, you can get the filter to sit pretty much as close as the clip filter does.

[DaveGarland]

Thanks fellas, that's my problem sorted out lovely. And thanks for the pictures Russell. All I need now is to get some grub screws from B&Q

[russellhq]

If you struggle to get them in B&Q, I got mine from ebay:

http://www.ebay.co.uk/itm/180819422501?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649#ht_2826wt_906

[jmbillings]

I think I am looking for the same thing here. Currently I attach my DSLR with this lot:

The part on the right is needed to convert the M42 1mm thread on my TAL focuser to the M42 .75mm thread that's more common and used in the adapter.

I'd like to get a LPR for helping with long exposure images; but mostly I only see 1.25" or 2" ones to fit on eyepieces- with my DSLR though, I'm not using an eyepiece. I can't get the clip ones as they only seem too be for Canon, and I use Sony.

Is a 2" eyepiece thread actually the same as the M42 mount? I'm guessing not as checking with a ruler it looks more like about 1.6" or so...

What does everyone else use?

[earth titan]

I debated long and hard about which LP filter. In the end the CLS filter won out. Although expensive, it is fit and forget.

Mine has been in my AP camera for what seems like ever and never comes out. The filter is very good performance wise also.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[kirkster501]

Is the Clip filter easy enough to take out so I can use my 1100d camera for terrestrial? I have been following this thread closely since I have a Baader UHC filter but 1.25 only.

I am not sure what the grub screws are meant to be doing guys? Also, by dropping down to 1.25 is some of the light cone being "wasted"?

Rgds, Steve

[earth titan]

The clip filter is very easy to remove.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[russellhq]

If you use the original thumb screws that came with the 1.25" holder, you can't fit the assembled unit into the focuser. So I bought some M3 grub screws from ebay (99p) and it all works.