wanted: microscope with long working distance (>=200mm)

[jcmaxwell]

I am looking for a microscope for rework in a professional lab environment, I can spend around 2000 EUR for it.

Most importantly I would need a working distance of at least 200mm, better 250mm. I almost exclusively work on heavy copper PCBs (6 layers 2oz etc.) and often solder them preheated on a hot plate which already consumes 100mm of the working distance.

EDIT: I might have chosen some incorrect vocabulary here. The optical working distance would be fine at 100mm to 150mm, but the stand (mechanical working distance, if you want) needs to be able to accommodate for the distance consumed by the hot plate arrangement.

Further points:

• boom stand
• magnification and zoom for wide range of component sizes from 0402 to TQFP-144
• trinocular with cam would be highly preferred, but not mandatory
• available to buy in Europe

Could somebody recommend anything?

[jfiresto]

I might look at something like a Meiji Techno EMZ-5H or EMZ-5TRH with an 0.3X lens (and 252mm working distance) if you want something new, durable and well supported. Will 13.5X maximum, total magnification be enough?

EDIT: You can probably use 15X oculars if you need up to 20X.

[Electro Fan]

At the end of this post is an attached chart that gives some working distance info.  The post and thread might have some of the other info you are looking for. 

https://www.eevblog.com/forum/beginners/the-ergonomics-of-microscope-soldering-direct-optical-view-vs-cameramo-257888/msg3332530/#msg3332530

[KrudyZ]

I would recommend something like this:

https://www.ebay.de/itm/175195255447?hash=item28ca737297:g:sK8AAOSwUsdiKvIu

[jfiresto]

That looks like a five-step M3C with high eyepoint 10X/21B oculars and an 0.63X objective giving a 149mm working distance and 4, 6.3, 10.1, 15.8 and 25.2X total magnifications. Substituting an 0.32X objective would halve the total magnifications and increase the working distance to 297mm.

The double-arm boom stand is really nice until the teflon sleeves wear through. Then you have to lift the microscope and unweight the arms to slide it horizontally. Since it is listed as gebraucht (used), the seller is expected to pay for the return shipping if anything is wrong with it.

[jcmaxwell]

Thanks everyone for your inputs. I will probably now order a Leica M60 with 0.8 Barlow lens and the XL stand. I need to spend more than I wanted, but it quality seems to be top notch.