SX CCD Filter wheel OAG head scratcher.

[Earl]

The SX Filterwheel and OAG have a backfocus of 17mm (OAG Head) + 25mm (Wheel with adapter)

SX cameras backfocus is 17mm +/-1mm

Total of 59 +/-1

As most reducers are 55 +/-1mm this setup will not work.

Im somewhat puzzled as to why is the case.

Can the adjusting plate be removed to save some mm?

[cfpendock]

What scope and reducer are you using?  I use an SX filter wheel and OAG with an FSQ106 and can find focus both with the Tak extender and reducer using an Atik 4000 (back focus 18mm). 

Chris

[Earl]

The Tak reducer has a more generous 72.2mm spacing so its not an issue.

Luckly im using this setup on a ZS71 and the spacer on the reducer is the same thickness as the OAG so I can still get the spacing right, however thats lucky as most reducers do not have the spacer to pad it out.

I need to be able to remove the setup and attach it to another reducer setup (c9.25 with antares .6x reducer) so taking of the OAG every time to get spacing would be a real pain.

[steppenwolf]

The SX Filterwheel and OAG have a backfocus of 17mm (OAG Head) + 25mm (Wheel with adapter)

SX cameras backfocus is 17mm +/-1mm

This was certainly the case with the original SX FW + OAG. Their new SX mini filter wheel + OAG is an integrated unit and is designed specifically for use with the 17.5mm backfocus of their CCD cameras and has a total depth of just 37.0mm.

It never ceases to amaze me though, how manufacturers still cling to the 'DSLR standard' of 45mm (DSLR backfocus) + 10mm (Adaptor), totally ignoring the requirements of CCD and field flattener users!!! CRAZY OR WHAT?

[Helen]

This was certainly the case with the original SX FW + OAG. Their new SX mini filter wheel + OAG is an integrated unit and is designed specifically for use with the 17.5mm backfocus of their CCD cameras and has a total depth of just 37.0mm.

It never ceases to amaze me though, how manufacturers still cling to the 'DSLR standard' of 45mm (DSLR backfocus) + 10mm (Adaptor), totally ignoring the requirements of CCD and field flattener users!!! CRAZY OR WHAT?

+1

[ollypenrice]

This was certainly the case with the original SX FW + OAG. Their new SX mini filter wheel + OAG is an integrated unit and is designed specifically for use with the 17.5mm backfocus of their CCD cameras and has a total depth of just 37.0mm.

It never ceases to amaze me though, how manufacturers still cling to the 'DSLR standard' of 45mm (DSLR backfocus) + 10mm (Adaptor), totally ignoring the requirements of CCD and field flattener users!!! CRAZY OR WHAT?

Totally crazy, but they cling to obsolete camera technology  at the design stage. Readers of the TEC website will be overwhelmed with joy to know that the reducer will cover a medium format Pentax film* camera and is designed to fit one, though CCD adapters are available from Astro Physics (and then you need a custom spacer.) 

Olly

* A photographic medium popular in the last century and involving (vaguely) light sensitive emulsions supported on celluloid and sometimes hypersentized at monstrous inconveenience in a portable laboratory.     

[Earl]

I appreciate the 55mm standard, I know its DSLR routes however conforming to both DSLR and CCD users makes sence. (reducer / flattener spacing)

To fix the issue with a 5..... posisiton wheel is sticky tape at best and yet again limits user options. My understanding is when you fix a problem you really dont try and make another problem at the same time.

I wanted to go SX as I had the Filterwheel and OAG so decided to have it all matching, in hindsight I should not of assumed it would be a useable configuation, and researched it better.

Glad I orderd a QSI6120 for the new year none of this sillyness to deal with.

[Horwig]

Glad I orderd a QSI6120 for the new year none of this sillyness to deal with.

Oh, at last, someone who's ordered one, it's on my shopping list (ssh!!!, don't let on, finances have not been cleared). Look forward to hearing your views of it.

Huw

[Sp@ce_d]

Tell me....

I have both the 5 & 7 SX FW's. I ordered the 7 after having the mini 5 for a while & liking not having to have a separate power cable as that's the only thing I don't like about my Atik EFW2 (well maybe the price too!). I didn't think too closely about the difference in spacing between the 5 & 7 though. Just as well I've got one the Atik 314's on it so only 13mm & a small chip means I'm just getting away with it. 

Oooh... nice one Earl..  Looking forward the seeing some results from the 6120 then.

[Earl]

INterstingly enough the ATIK setups Camera, wheel and OAG have the same backfocus of 59mm