Barlows??? Education required please.

[Flash2Bang]

Hi,

What are barlows and how will they help me. Probably an old question already been answered somewhere I guess. However I have seen these in 2x and 3x Barlows. How high do barlows go and what are the pro's con's of having them. When will I need one/two/three etc and how do I use them. Phew! Steep learning curve. Sorry for the bone question.

Andy.

[JamesF]

Barlows increase the effective focal length of your OTA by the factor given on the barlow. So, a 2x barlow would double the effective length. GIven the same eyepiece this will double the magnification. It's not uncommon to see barlows with factors of up to 5x, but the higher ones are perhaps more useful for imaging.

Generally my personal preference would be to buy another eyepiece of the required focal length rather than a barlow, but it can be a useful way to "get two eyepieces out of one" if you need to.

James

[Flash2Bang]

Thanks James

I think I will invest in one of these.

PS Dont take this the wrong way but what is OTA?

[nightfisher]

OTA is short for optical tube assembly, what scope (OTA) do you own

[Flash2Bang]

Meade ETX125 ( so a 5" OTA?)

How do I Place this at the bottom of the posts like everyone else?

[nightfisher]

Meade ETX125 ( so a 5" OTA?)

How do I Place this at the bottom of the posts like everyone else?

you click on your username at top right, click profile then click edit profile, on left side you will see a box with signature, click that and you should see edit signature, type what you want and submit

[Friedberg]

Go to edit your profile and on the left side of the screen you will see "signature" click on that to edit or add your signature witch most members use to list their equipment on. "Cheers"

[farunj]

Also keep in mind that the barrows will reduce the brightness of the image!

[CSM]

The maximum magnification for a 125mm scope is around 250 which, if this is the f/15 scope, would be achieved with a 7.5mm eyepiece of a combination of eyepiece plus Barlow. As mentioned before the higher the Barlow the dimmer the image and with a f ratio like that you may be better off getting single eyepieces. Alternately try a zoom lens and see how you get on. The Skywatcher 7 - 21mm range offers you 7, 9, 11, 15 and 21 for only around £40 and with reasonable quality.

[Flash2Bang]

All good advice! Thanks. The only eyepiece that came with this is a 26mm super plossl and has gave good planetary and M3 / M5 cluster views.

Thanks for the info on the signature block too!......Hopefully wont be a newbie forever and we all start somewhere