Pentax 14 XW arrived!

[jamieren]

Had a chance to take a look at the almost full moon tonight. Along the top (bottom actually, it is a reflector) I could clearly see craters. They looked like several waterless monochrome lakes. I put my 10mm speers-WALER in after and could see a decrease in image quality. It's hard to put my finger on it, but it just seemed the image was a bit sharper in the pentax (and it ought to be at 3x the price!).

On that note... when I was young & dumb (2 months ago) my kids got some finger prints on the lens. I thought cleaning was simple, the old 'breath and wipe with a lint free paper towel'. Now however I know such actions constitute tempting of hellfire in astronomy circles. When viewed at an angle from 1 or 2 ft away I noticed (as it had some condensation on it) that it had streaks across it, not unlike a window that gathers moisture in the winter, comprised of alternating green and purple (the coating no doubt). I'm hoping this is evidence of a shoddy cleaning job and nothing more. It's not possible that I marked up the lens, is it? I've heard that a solution of 50/50 distilled water & isopropyl alcohol with a drop or two of dishwashing liquid is a good cleaning agent.

Any suggestions?

[Andrew*]

Had a chance to take a look at the almost full moon tonight. Along the top (bottom actually, it is a reflector) I could clearly see craters. They looked like several waterless monochrome lakes. I put my 10mm speers-WALER in after and could see a decrease in image quality. It's hard to put my finger on it, but it just seemed the image was a bit sharper in the pentax (and it ought to be at 3x the price!).

On that note... when I was young & dumb (2 months ago) my kids got some finger prints on the lens. I thought cleaning was simple, the old 'breath and wipe with a lint free paper towel'. Now however I know such actions constitute tempting of hellfire in astronomy circles. When viewed at an angle from 1 or 2 ft away I noticed (as it had some condensation on it) that it had streaks across it, not unlike a window that gathers moisture in the winter, comprised of alternating green and purple (the coating no doubt). I'm hoping this is evidence of a shoddy cleaning job and nothing more. It's not possible that I marked up the lens, is it? I've heard that a solution of 50/50 distilled water & isopropyl alcohol with a drop or two of dishwashing liquid is a good cleaning agent.

Any suggestions?

Not the best way to clean eyepieces, I admit. But modern coatings are pretty tough and I would be surprised if you actually managed to scrape off some coating.

WRT cleaning, fingerprints are oily. Using water to attempt to remove them will only smear it. Some kind of alcohol is essential. You could use 99%+ IPA and Q-tips to clean it. Don't worry about diluting it or adding washing-up liquid. Use one Q-tip per wipe to avoid dragging anything across the surface and scratching it. Oh, and blow or gently brush as much dust as possible off the lens before wiping with anything.

Glad you like your Pentax - I bet they are stunning eyepieces but I still haven't managed to get a view through one.

Andrew

[mightymonoped]

No doubt I'll incur the wrath too but...this is the method I used on my EP's and Barlows...and it worked very nicely.

I bought some Baader Optical Wonder fluid (around £11) which comes with a very good micro-fibre cloth.I sprayed some of the fluid on the micro-fibre cloth then wrapped the cloth over a cotton-wool cleaning bud to make a micro-fibre cleaning bud in effect.I then used this very carefully and gently to swab the eyepiece lens.

The results were like new, grease, dirt and dust bunnies all gone.

Not a bad investment for £11 in my book.

Tony

[mcrossley]

Sounds OK to me Tony, as Andrew said most modern coatings are pretty resilient. Keep that micro-fibre cloth clean though. A note of caution on cotton buds and alcohol though; the alcohol can part dissolve the glue used to attach the cotton to the stick on some of them and then deposit a thin film on your lens (been there done that!), I prefer to use lint free clinical wipes. One gentle wipe then use a new section for the next wipe etc, then bin it.

Mark

[Rob]

Optical wonder and the microfiber cloth - ONLY!. Dont press the cloth too hard and optic brush the lens (lightly) first.

[jamieren]

the alcohol can part dissolve the glue used to attach the cotton to the stick on some of them and then deposit a thin film on your lens

Mark

I think this is what I experienced. After unsuccessfully trying several times to use the Q-tip & isopropyl method I finally just gave it a good breath and used a couple of clean Q-tips. Viola! The lens is now clean and free of streaks. Either the "glue" as Mark said was being dissolved and left behind, or the alcohol itself was leaving a residue. Now to check the performance of that speers-WALER in comparison to the pentax again...

[Ben Ritchie]

I believe Alcohol does leave a residue, although it doen't affect performance - apparently a wipe with acetone cleans that off if it bothers you.

[jamieren]

For all the talk of how easy it is to damage the coatings on your eyepieces I'm surprised. High % alcohol, acetone... I think these coatings are far more impervious than most people admit! Of course who would want to take a chance with a $300+ eyepiece? Not I, that's for sure. If the breath & Qtips keep working that's what I'm gonna use, if anything at all!