Star flare in binoculars

[breammaster (Wey)]

Hi,

I recently obtained a pair of Pentax 10x50 SP WP binos. Upon testing them over the past two nights, I noticed that the brighter stars had a noticeable flare or spiking to them. I wonder if there is something wrong with the binos or is this cause the seeing was bad that night. It's been quite windy the past two nights. Also, is it possible that if my eyes are tired, the flaring can happen? I had some Nikon Aculons which I swapped for these and I didn't notice this flaring as much. But the n ights which I took out the Nikons were not windy.

[Atmos (Colin)]

I might be ordering a pair next week so I'd be interested to find out too

What are your thoughts on them otherwise?

[breammaster (Wey)]

Also, I noticed my exit pupils are perfectly round. There is some slight squaring of the edges. These are the updated version of the pentax PCF wp ii. So i wouldn't expect that.

[breammaster (Wey)]

Originally Posted by Atmos

I might be ordering a pair next week so I'd be interested to find out too

What are your thoughts on them otherwise?

So far, I love viewing through these more so than my 8 inch DOb. I don't know what it is, but the rich field views and ease of set up make these enticing. The sharpness to the edge is quite good. I think about 80% out and there is slight distortion. The Nikons I had previously had a huge amount of edge distortion from about 60-70% out. These Pentax(with exception of this star flaring issue) are great for using almost the entire field of view. Color is a little bit flatter than with the Nikon Aculons. I'm not sure if that's because these have better color correction?? I'm only new to Binos.

The unperfectly round exit pupil thing weirds me out though. I wonder if this was a bad batch. I couldn't get my hands on the older PCF wp ii model. They are discontinued.

[julianh72 (Julian)]

Never mind - Oops!

[breammaster (Wey)]

Took them out tonight and had a much better session. Super sharp views. Brighter stars still exhibit a bit of radial spikes but not a big deal. The views are very asthetically pleasing. I did try to spot comet linear 252 but i could barely see it with averted vision cause of full moon.

Binos + recliner chair + headphones = Bliss

[brian nordstrom (As avatar)]

For binoculars of this quality there should be zero flaring !!!!.
If it was me I would send them back now , I can guarantee you that it will start to irk you so send them back .

You will be glad you did when you see images that are clean and clear.

Brian.

[breammaster (Wey)]

Hi Brian,

I exchanged them for another pair. It's still the same. I think the correct term was radial spikes. It's the brighter stars like Sirus and Canopus that show it the most. Small and short spikes that look like the diffraction spikes on a reflector. The lower magnitude stars don't seem to show it as much. I can still split all the doubles of crux. I can also split Mu1 Crucis. I think it's just the binocular design.

[brian nordstrom (As avatar)]

Are you sure its the binos , not your eyes ? .

Not a silly question as a good pair like yours will exagerate any aborations in your eyes ( like floaters ) , have you had them checked lately ? .
The view should be clean and sharp at 10x , something aint right here sorry to say .

These are good qualiy binoculars , something like this you will see in those cheap EBay pairs you see there all the time .
Not these .

Also a tripod will help no end and yes bright stars will show a little but it should be very subdued .

Brian.

[ausastronomer (John Bambury)]

Hi Wey,

Have you adjusted the diopter adjustment properly before you started to use and refocus them?

Cheers,
John B

[breammaster (Wey)]

Originally Posted by brian nordstrom

Are you sure its the binos , not your eyes ? .

Not a silly question as a good pair like yours will exagerate any aborations in your eyes ( like floaters ) , have you had them checked lately ? .
The view should be clean and sharp at 10x , something aint right here sorry to say .

These are good qualiy binoculars , something like this you will see in those cheap EBay pairs you see there all the time .
Not these .

Also a tripod will help no end and yes bright stars will show a little but it should be very subdued .

Brian.

It could quite possibly be my eyes. I haven't had them tested in years. I'm getting a tripod adapter today though. I'll see if it helps.

[breammaster (Wey)]

Originally Posted by ausastronomer

Hi Wey,

Have you adjusted the diopter adjustment properly before you started to use and refocus them?

Cheers,
John B

Yep. I did the left Barrel focus. Then set the right Barrel focus with the diopter.