Quote:
Originally Posted by Hemi
Thanks Don,
I thought they were the same EP from your previous advice, but my impression was that Stellarview have a very well respected (superior?) quality control process, hence chose that. Lighter would definitely be better, as it will often be used in the Fs60q.
Another reason is that no one seems to have the apm.
Does the 20mm field stop in the APM vs the 23mm Field stop in the TV and SV make a significant difference?
Hemi
|
We don't know the actual field stop dimension in the 13mm APM.
The 13.5mm Stellarvue is 22.6mm, which is probably what the APM is.
The TeleVue Ethos is 22.3mm, and I would bet the KUO 100° eyepieces are equal to each other.
I know APM has 20mm for the field stop on their website, but I distrust the accuracy of that figure. That would make it 10% narrower than the Ethos, which it isn't.
APM is getting more 13s at the end of March.
Weight is
13 APM--461g
13.5mm Optimus--581g
13mm Ethos--590g
Both of the latter have stainless steel bottom barrels.