Posts Made By: dan hilts

Only that the zonal errors in the objective weren't detectable using the 10mm eyepiece but did show at higher power using the 3.2mm eyepiece.

dan

I love Myrtle Beach,(and I don't golf). Great shot, brings back a lot of good memories.

dan

I bought a $100 point and shoot digital camera for my wife last year so she had something to take on a vacation trip. She loves it. It is a perfect match for her skill level and she has a ball with it. I tried some 15 second star shots with it and found that it was useless for that. There were far more hot pixels than stars recorded. But in good light it takes a great shot and has a nice macro feature as well. Nice thing is, I don't get worried when I see it lying around or tossed into her bag without its case. So far it has more than paid for itself in the price of film not purchased. I wouldn't sweat it over the cost of the Canon. She'll enjoy it more than you know.

have fun,
dan

I would think there would be exit pupil problems. At lower power the exit pupil is huge. 30X provides an 8mm EP. To get a 5mm EP requires 50X which can be obtained with a 15mm eyepiece. Any brightness at all in a target will require smaller exit pupils for visual use or there will be a waste of aperature. So why not just use the smaller aperature to start with and save the expense of big glass and big mounts?

The question remains as to the optical quality of the lenses when viewing at higher powers with reasonable exit pupils. The lens was probably designed for large wide flat field imaging and as such, on axis images were likely compromised to improve the edge of the field and flatten the image plane. At 50X viewing, star images may begin to soften noticeably.

I could be wrong but I doubt these lenses would make a sucessful bino.

dan

Then this one is not a bargin?

http://www.parksoptical.com/product_info.php?cPath=21_116&products_id=466&pname=PRT2+60

dan

This one is twice the price!

http://www.parksoptical.com/product_info.php?cPath=21_116&products_id=467&pname=PRT46+60mm+EQ+System

Hard to image they actually list this 60mm at $2800, discounted to $1,999. It does include a 25mm Kellner eyepiece though. That ought to be worth something.

It seems that the only difference between the PRT1 and PRT2 is the slo-mo on the ALT-AZ mount. For that there is a $500 difference in price.

dan

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Yes, I think so.

For some technical explanations regarding the effects of seeing with two eyes, look up some of the stuff written by Ed Zarenski both on AM forums and CN (maybe elsewhere as well!).

I have one of the Chinese binoviewers that came out about two years ago. It doesn't ever give a 3D effect but it sure is comfortable using two eyes to observe. Whenever I plan on some extended lunar views or spending some time on Saturn, I drag it out. My wife who is not an experienced observer but will take a quick peek now and then really likes the wow factor of the bino viewer. It is so much easier for her to see things when she can relax and use both eyes.

My refractor is F12.5 with enough in focus that I can use the bino viewer without using a Barlow. I don't have an expensive eyepiece collection but Plossls work quite well on my setup as will Kellners. I also have a pair of the 9mm Expanse from Orion.

I can only assume there may be quality issues with some of these inexpensive bino viewers. Mine is actually quite nice and I don't notice any degradation of the images or additioanl false color. Aligning the images to my eyes has not been a problem. If you buy one, get it from a reputable dealer so any issues will be taken care of. I think Wo and SV still have them, Smart Astonomy doesn't list them anymore. Anacortes carries the WO unit.

clear skies,
dan

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Hi Greg,

Have you considered a 6"-8" Newt on a Dob mount with DSC? Something like the Orion IntelliScope? It can be used in with or without the computer operation.
Still needs proper cool down though.

dan