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View Full Version here: : P-FLAT 4 with ED80


adman
22-09-2010, 09:50 PM
has anyone used the william optics p-flat 4 flattener with an ED80. I am going to be using it with a canon 550D, and am wondering how it performs - specifically in regards to vignetting?

I am currently using the orion flattener/reducer that screws directly onto the drawtube. It provides a great secure mount, but there is nowhere to put my lovely 2" IDAS LPS filter

Cheers
Adam

troypiggo
23-09-2010, 01:03 PM
I've had no troubles with it. See here (http://decluttr.com/4516793959) and here (http://decluttr.com/4193134539). Taken with SW ED80, WO FFIV, and 40D. Not the best photos, but nice flat field to my eyes.

Logan (logieberra) tried it with a Pentax (I think it was) camera and had an issue with it clashing with the camera body, and also had some issues with the flattener itself that appeared to be one of the lenses inside it installed around the wrong way.

I'd think the 550D should be ok. Only think I'd check is the pointy flash lid thingy that sticks out over the lens - make sure that clears the FFIV. I have my wife's 350D at home that I could check to make sure it clears. Will try to remember this weekend.

adman
23-09-2010, 01:25 PM
thanks for that Troy - I had forgotten about the troubles that Logan had with his Pentax. I would assume the the 550D has a similar profile to other EOS's....?

Adam

troypiggo
23-09-2010, 02:04 PM
Should be close in profile, but the 550D and others in that series are smaller bodies than the 40D etc.

Logieberra
23-09-2010, 05:11 PM
If I had my time around again... I would go with the Orion / Skywatcher reducer/flatterner for proven compatability.

However, there's no denying that Troy has had great results (see last month's Australian Sky & Telescope)...

I never got to the source of the problem. Thankfully William Optics came to the table and worked with me. Full refund in the end.

Logie.

multiweb
23-09-2010, 05:36 PM
+1 . P-FLAT IV for me. Go the ED80! :thumbsup:

adman
23-09-2010, 07:21 PM
Thats what I have at the moment - but where do you put the filters - there is nowhere to screw a 2" filter in....:shrug:

In fact - Marc - is there somewhere to put 2" filters on the p-flat IV??

Adam

multiweb
23-09-2010, 08:13 PM
Yep. M42 thread on focuser side.