Choosing a Laptop for Astronomy

Introduction

We are often asked which laptop to buy for astronomy. Lee has been looking into this with a view to buying one for himself so offers this advice to others in a similar position. Please note that hardware and software are constantly being improved so do call us if you want up-to-the-minute advice.

There are two aspects to using a laptop for astronomy, data acquisition and data reduction. Data acquisition includes real-time tasks such as controlling the camera, telescope and any related peripherals whilst data processing can be carried out later and on a different machine. However, it is often beneficial to do some data processing whilst observing as it allows you to get an idea of image quality.

Processor

The processor is at the heart of any PC/Laptop. The choice of processor depends on what you want to use your laptop for. For just image acquisition you do not necessarily need a powerful processor. An Intel Celeron or AMD Sempron would be sufficient. However if you want your laptop to be a dual-purpose acquisition and processing machine (e.g. aligning and stacking) a more powerful processing core would be beneficial such as the Intel Dual Core or AMD Turion X2 Dual Core processors.

One other note about processors. Some inexpensive laptops come with desktop processors which consume more power thus eating up precious battery life. Check to make sure which processor is inside your choice of machine.

Memory

Many laptops come with 1Gbyte as standard. This will allow you to run the vast majority of applications. The more memory you have the more applications you can run without slowing the computer down. This is important when using intensive applications such as Registax where you can have many hundreds (or thousands) of frames that need to be aligned and stacked.

Screen Size

Laptops typically come with 14.1", 15" and 17" displays. If you have a large screen you can certainly display bigger images which is ideal for showing others your prized astrophotos! However you can also take advantage of the larger screen size as you will be able to display more information such as the display from a guiding camera as well as the information being recorded by your imaging device. Having a larger display also can help with critical tasks such as focusing. However, on the down side, bear in mind that a larger display consumes more power thus shortening your battery life.

Graphics Card

Some desktop PCs and laptops come with graphics cards that are integrated onto the motherboard (the electronics board that the processor, memory and other devices fit onto) and they use a portion of the system memory to process and store graphics information. Although this may seem like a good idea, system memory processes graphics information slower than dedicated graphics cards with dedicated (faster) memory. Try and choose a machine that has a dedicated graphics card.

Hard Drive

60Gbyte minimum. An increasing number of laptops are now coming with 60Gbyte minimum. However the larger the hard disk the more images (both raw and processed you can store).

Cost

You can buy a decent image-acquisition laptop for about £350. These machines have a Celeron/AMD processor, 15" screen, 80Gbyte Hard drive, 1Gbyte memory. However for about £500 you can get a machine with Intel/AMD Dual Core processor, 17" display, 2Gbyte Memory, 256Mbyte Graphics Card and 120Gbyte Hard Disk.

Please note that prices change rapidly and these are offered as a comparison to show the relative prices of a machine suitable just for data acquisition and one suitable for data reduction as well.

Lee's Ideal Dual-Purpose Laptop

• Processor: AMD Turion x2 or Intel Dual Core
• Memory: 2Gbyte
• Graphics Card: Nvidia dedicated graphics card with 128Mbyte/256Mbyte
• Hard Drive: 120Gbyte
• Screen Size: 17" Widescreen

Windows XP or Vista?

At the time of writing most new laptops are supplied with Vista so you don't really have much choice, but, some of the software supplied by equipment manufacturers doesn't yet run under Vista. Most of the major image processing packages do, but please contact us if you are in doubt.

What about Apple?

Much of the astronomy software provided by manufacturers runs only under Windows so we haven't considered Apple. Unfortunately, life is too short to cover everything.