The Sun - 12th May 2015

[David Smith]

Managed to grab the usual DSLR white light before work this morning. When I got home my new Revelation 0.5x reducer had arrived so decided to plug it in and have a go with the QHY5. I had hoped the reducer would give me a full disk with the QHY5 but sadly that has proven not to be the case. Are they sensitive to spacing in the same way as a barlow? Was all done in a hurry tonight as the Sun was sinking fast and I was supposed to be cooking dinner not playing with my toys

Usual DSLR full disks first

20150512 by David_The_Bears_Fan, on Flickr

20150512mono by David_The_Bears_Fan, on Flickr

Full disks (almost) with QHY5-II mono and 0.5x reducer. Seeing was much worse this evening compared to this morning so not really fair to compare but good to get a first go.

Registax FD by David_The_Bears_Fan, on Flickr

imppg FD invert by David_The_Bears_Fan, on Flickr

And finally the big AR with the QHY5 and Revelation 2x barlow instead of the reducer

AR2339 Barlow by David_The_Bears_Fan, on Flickr

[durr]

Thanks Dave was just checking your images (always do ) to see where the spots were. Not much sun here but tomorrow!!!!

[Luke]

Nice work, Dave If you have the same 1.25 inch 0.5x revelation reducer as me (about £20?) then it is very sensitive to distance from the chip. I think in a similar way to the Antares one (never sure which brands are the same thing or not):

http://agenaastro.com/antares-1-25-0-5x-focal-reducer.html

What's your rough distance from the chip to the reducer? I get about 0.72x reduction with my ASI174 and 0.55x with my Grasshopper 3, due to the difference in distance to chip. The ASI I had to nudge up to avoid strong vignetting with my Quarkus Maximus Chromospherus (I cut the nosepiece down to lessen the reduction).

[David Smith]

Thanks Dave was just checking your images (always do ) to see where the spots were. Not much sun here but tomorrow!!!!

Forecast here tomorrow is poor and I have a long day work wise tomorrow so I may be looking for your images for reference tomorrow

Nice work, Dave If you have the same 1.25 inch 0.5x revelation reducer as me (about £20?) then it is very sensitive to distance from the chip. I think in a similar way to the Antares one (never sure which brands are the same thing or not):

http://agenaastro.com/antares-1-25-0-5x-focal-reducer.html

What's your rough distance from the chip to the reducer? I get about 0.72x reduction with my ASI174 and 0.55x with my Grasshopper 3, due to the difference in distance to chip. The ASI I had to nudge up to avoid strong vignetting with my Quarkus Maximus Chromospherus (I cut the nosepiece down to lessen the reduction).

Sounds like we have the same one then Luke. Once I have the c-mount to 1.25" adapter in place (I need this so I can thread the reducer in) I would say the spacing is around 30mm from the front of the chip to the back of the reducer lens. Does the reduction increase or decrease with increasing distance from chip?

[Dave Smith]

Excellent David. This lot comes out really well in white light.

Dave

[sooot]

Very nice david

[Luke]

David, the reduction strength gets stronger (more and more reduction) the further away the reducer is from the camera chip. So you need to increase the distance.

With my Grasshopper 3, I would say the distance from the camera chip to the first edge of the reducer's glass is about 39mm and gives me about 0.55x reduction. I would guess the figure given for the Antares of 47.5mm from the centre of the lens assembly to chip for 0.5x reduction sounds about right for the Revelation too? I love this little reducer

[David Smith]

Thanks all for your kind comments

@ Luke

Just had a bit of a work out. Based on the images I took today I am getting about 0.56x with current spacing arrangement. Glad I need to increase the spacing, that's easy to do. More playing required! Thanks for your help

[Chris]

Really like the added close up Dave, plus the other images of course

[michael.h.f.wilkinson]

Very nice work!

[Johan L]

Great set

[Pete Presland]

Looking very good hopefully catch this Active region today before the poor weather arrives again!