Powermate advice needed for my Megrez 72

[gost]

I have a WO Megrez 72 with a Lunt 50mm front Ha filter. I would like to get more detailed shots with my DMK31 camera.

Will a 2.5x powermate be enough or should I go for the 5x? Or will the 5x be to much for my setup? I have a 600 blocking filter.

[ollypenrice]

I have the LS60 and am thinking about a Powermate. I think 2.5 will need good seeing so more than that I wouldn't want to risk.

I have the 1200 filter but I don't know how much the 600 restricts you.

Olly

[Merlin66]

A x2.5 powermate would work, but the 6mm blocking filter aperture may give you vignetting.... it's designed for a 500mm focal length not 500 x 2.5 = 1255mm fl....

[Technobill]

I have a WO Megrez 72 with a Lunt 50mm front Ha filter. I would like to get more detailed shots with my DMK31 camera.

Will a 2.5x powermate be enough or should I go for the 5x? Or will the 5x be to much for my setup? I have a 600 blocking filter.

Hi Olly,

I have a 2.5 powermate that I use wth my Lunt LS60. I couldnt imagine using a 5x with that. I dont think there is enough light gathering power to be able to magnify it that much.

If I double stack mine the exposures I need to get reasonable details of proms etc when using the 2.5 as well are down to about 19 to 15 frames a second. Any slower and I think you would rarely get clear images unless seeing was exceptional. I have tried a 2x barlow inside the 2.5 powermate and the results were pretty poor.

I am not sure how much od the disk you are seeing now. Bit if you go to my website Billy D's Front Page on my home page the latest images were taken with the 2.5 pm, fursth down the page they were taken with a 2x barlow. Keeping in mind I use the DMKK41 that has the bigger chip and I get to see nearly the entire disk without a barlow.

Do you have access to a barlow? you can always try a cheapie barlow first. I feel the power mate is substantiually better, so if you cant afford it I would not wast desperate funds on the Barlow.

In Summary I reckon with a 5times there would be rare occassions when the results would be adequate as seeying would play a much better part. Where as with a 2.5 you get to see nice details and is can be used under most circumstances.

Bill D

[gost]

I have 2x barlow today and would like a bit more reach and the best quality.

Next investment should be a bigger blocking filter.

What you guys think of the Megrez 72 as a solar imaging scope? With a 2.5x I will have a 1080mm/f15 scope.

[brianb]

The Megrez 72 is f/7.5 which is very similar to the f/7 (FLT110) and f/8 (Solarscope 60) scopes I use for solar imaging.

IMHO x5 would be "too much", x2.5 will be fine though you may on occasion want a bit more. I never did find a 3x barlow / tele-extender that I liked so my advice is to look out for a 4x Imagemate ... they do turn up occasionally, usually seem to give effective powers between 3.5x and 3.75x rather than 4x (this is actually a useful "flaw") and work rather well.

The Televue 2.5x Powermate is the one "optional" item in my imaging kit I'd feel lost without ... well worth the money IMHO though if you're a cheapskate the Celestron Ultima SV 2x barlow gives very similar results (and almost exactly 2.5x with an Imaging Source camera).

If you have the Powermate after the blocking filter, the smaller size not matching the effective focal length at the camera doesn't matter.

I've not used the Megrez 72 for solar imaging but it ought to work pretty well ... a bit limited in aperture for "white light" work but it should work very nicely indeed with a 60mm aperture etalon stuck on the front.

[gost]

Sounds great.

Just to clarify, Megrez 72 is a f6 scope

http://www.williamoptics.com/telescopes/megrez72_spec.php

[brianb]

Megrez 72 is a f6 scope

Ah, my bad, I divided 1040 by 2 instead of 2.5.

5x (f/30) might be usable when the seeing is unusually steady.

With my scopes, "4x" is usable about 1 day in 10, 2.5x is OK about half the time and the rest of the time I wish for less rather than more.